Verbal encouragement was provided throughout the period of effort which did not exceed 10 seconds. Results were recorded in kilograms kg , the mean of three trials for each hand was recorded and the highest value of the two means was used for further analyses [ 32 , 33 ]. Continuous data were assessed for normality using Shapiro Wilcoxon tests and visual assessment of histograms.

Descriptive statistics were reported as means ± SD for parametric data, and frequencies and percentages for categorical data.

Differences between groups were analysed using independent t-tests for parametric data, and the chi-square test of independence for categorical data. The measurements were categorized into two groups according to sex.

The measurements were further categorized according to body fat percentage into two groups. A multiple linear regression analysis was performed to determine body composition parameters predicting muscle strength in males and females.

Adjusted r, standard error values, and multicollinearity statistics were used to identify the most appropriate equations. This analysis was undertaken in males and females according to obesity classifications based on body fat percentage.

All statistical analyses were completed using the statistical software IBM SPSS version Descriptive statistics for the study population according to sex are presented in Table 1. The mean ± SD age of participants was Males were taller, heavier and had a lower body fat percentage than females, but these differences were not significant.

The mean BMI for this study population fell in the overweight BMI category Using BMI categories, In males and females, 9. The prevalence of low muscle mass was 2. Appendicular skeletal muscle mass index and muscle strength were higher in males compared with females, this difference was significant for muscle strength only Table 1.

When exploring the association between muscle strength and muscle mass according to obesity classification using body fat percentage, muscle mass was significantly associated with muscle strength in non-obese males and females.

However, in participants with obesity, muscle mass was no longer associated with muscle strength Tables 4 and 5. In this cross-sectional study, we evaluated the relationship between muscle strength, muscle mass, and body fat percentage in older adults living in Auckland, NZ.

The findings indicate that muscle strength was associated with muscle mass. The magnitude of this association was greater in males than females, with addition of body fat percentage slightly increasing the ability of the model to predict muscle strength.

When exploring the association between muscle strength and muscle mass according to obesity classification using body fat percentage, muscle mass was associated with muscle strength in non-obese participants. However, this association was not observed in older adults who were classified as obese.

This indicates that body fat percentage should be considered when measuring associations between muscle mass and muscle strength in older adults. We found a higher prevalence of participants with obesity using body fat percentage classifications This result was as expected, as BMI has been shown to underestimate adiposity in older adults [ 37 ].

A recent survey in New Zealand using BMI classifications reported that the prevalence of obesity in older adults between 65—74 years was The lower level of obesity reported in our population may reflect our recruitment inadvertently targeting healthy older adults. We also identified 3.

The lack of studies reporting the prevalence of low muscle strength and the application of different cut-off values makes it difficult to compare studies. In this cohort, we applied the updated cut off values of low muscle strength defined by the European Working Group on Sarcopenia in Older People EWGSOP2.

A nationally representative sample of Brazilians aged 65 years and older using the same cut-off values as our study observed a higher prevalence of low muscle strength Other studies which applied the older cut off values defined by the European Working Group on Sarcopenia in Older People EWGSOP , observed a higher prevalence of low muscle strength of The higher prevalence observed in these groups, is possibly explained by the inclusion of people older than 74 years, and a potentially less healthy population than those participants included in our study.

The prevalence of low ASMI was 6. The higher percentage in the study appears to be explained by the inclusion of adults over the ages of 74 years. Our results provide evidence that muscle mass is positively associated with muscle strength in older men and women.

This result aligns with the literature [ 43 , 44 ] and suggests that efforts to maintain muscle mass should have a significant effect on preserving strength in older adults.

When stratified by sex, we observed strong evidence that muscle mass was significantly associated, but not a major contributor to muscle strength in older men and women.

In a regression model taking into account muscle mass, it was shown that an increase of 1 unit muscle mass will increase the value of muscle strength by 0. These results highlight not only the importance of increasing muscle mass, but also the importance of decreasing body fat percentage to preserve muscle strength in older adults.

The cross-sectional nature of our data impedes any causal inference. Nevertheless, the results from our study provide justification for further prospective research that evaluates the effects of interventions, which are aimed at optimising body composition and muscle strength in older adults.

To our knowledge, this is the first study to investigate the role of obesity classification based on body fat percentage in the relationship between muscle strength and muscle mass.

Results from multiple linear regression analyses provide evidence supporting the important role of obesity classification according to body fat percentage when investigating the relationship between muscle strength and muscle mass. Our study demonstrated that when obesity was classified using body fat percentage, muscle mass was significantly associated with muscle strength in non-obese older adults.

However, an association between muscle strength and muscle mass was not observed in older adults categorised as obese. The accumulation of intramuscular lipid content or poor muscle quality , which is seen in people with obesity may explain the influence of obesity in the relationship between muscle strength and muscle mass.

Goodpaster et al. reported that higher intramuscular lipid content is associated with lower muscle strength, independent of muscle mass [ 45 ]. Also, accumulation of intramuscular lipid content is known to be associated with insulin insensitivity, inflammation and functional deficits in skeletal muscle.

It will be important in the future to continue to focus on understanding predictors of muscle strength in older adults with obesity in order to provide appropriate interventions to increase muscle strength. There were significant strengths to our study.

The relatively large sample size permits us to examine whether the relationship between muscle strength and muscle mass was similar in males and females. Also, it is possible that the inclusion of community-dwelling healthy older adults provides the opportunity to identify issues and promote preventative action in early old age.

Furthermore, the use of DXA is an accurate measure of body composition. However, in contrast to magnetic resonance imaging MRI or computed tomography CT DXA cannot detect intramuscular fat from muscle mass nor distinguish the composition of muscle [ 46 , 47 ].

This cross-sectional study limits the ability to detect causality; hence, only associations were discussed. Other limitations are the population group, which was not representative of the New Zealand population, as this cohort was composed of a convenience volunteer sample of men and women aged 65—74 years living in the community.

The classification by body fat percentage for obesity may also be perceived as a limitation given the arbitrary nature of the cut-off points.

Finally, we did not assess lower extremity muscle strength, which is a more direct predictor of falls. However, grip strength is associated with lower-body muscle strength [ 48 ] and a strong predictor of disability [ 49 ].

Muscle mass and body fat percentage were predictors of muscle strength in this cohort. Muscle mass was associated with muscle strength in non-obese older adults whereas, there was no association between muscle mass and muscle strength in older adults who were classified as obese. This indicates that obesity classification plays an important role in the relationship between muscle strength and muscle mass in older adults.

We suggest that this could be mainly attributed to muscle quality, which could be a contributor of muscle strength in older adults who are obese. Further research should focus on identifying predictors of muscle strength in older adults with obesity. We thank the REACH team including Cassie Slade for managing the recruitment of participants and data collection; and Karen Mumme, Harriet Guy, Angela Yu, and Nicola Gillies for assistance with data collection and data entry.

Browse Subject Areas? Click through the PLOS taxonomy to find articles in your field. Article Authors Metrics Comments Media Coverage Reader Comments Figures. Abstract Background Aging is associated with decreases in muscle strength and simultaneous changes in body composition, including decreases in muscle mass, muscle quality and increases in adiposity.

Conclusions Body fat percentage should be considered when measuring associations between muscle mass and muscle strength in older adults. Introduction Globally and in New Zealand the proportion of older adults is increasing [ 1 ].

Materials and methods 2. Study design This study was a secondary aim of the Researching Eating, Activity and Cognitive Health REACH Study. Study participants and procedures Participants included men and women aged 65—74 years, living independently in Auckland, NZ.

Data collection All participants visited the Human Nutrition Research Unit on one occasion for collection of data as part of the wider REACH study. Statistical analysis Continuous data were assessed for normality using Shapiro Wilcoxon tests and visual assessment of histograms.

Download: PPT. Table 1. Characteristics of study participants by sex a , b. Fig 1. Table 2. Results of multiple linear regression modelling on the relationship between muscle strength, mass and body fat percentage in older females.

Table 3. Results of multiple linear regression modelling on the relationship between muscle strength, mass and body fat percentage in older males. Table 4. Results of multiple linear regression modelling on the effect of obesity in the relationship between muscle strength and mass in older females.

Table 5. Results of multiple linear regression modelling on the effect of obesity in the relationship between muscle strength and mass in older males. Discussion In this cross-sectional study, we evaluated the relationship between muscle strength, muscle mass, and body fat percentage in older adults living in Auckland, NZ.

Prevalence of obesity, low muscle strength and low muscle mass We found a higher prevalence of participants with obesity using body fat percentage classifications Association between body composition and muscle strength Our results provide evidence that muscle mass is positively associated with muscle strength in older men and women.

The role of obesity classification in the relationship between muscle strength and muscle mass To our knowledge, this is the first study to investigate the role of obesity classification based on body fat percentage in the relationship between muscle strength and muscle mass.

Conclusions Muscle mass and body fat percentage were predictors of muscle strength in this cohort. Supporting information. S1 File. s SAV. Acknowledgments We thank the REACH team including Cassie Slade for managing the recruitment of participants and data collection; and Karen Mumme, Harriet Guy, Angela Yu, and Nicola Gillies for assistance with data collection and data entry.

References 1. United Nations, Department of Economic and Social Affairs, Population Division. Statistics New Zealand. A statistical volume, Wellington.

Robertson MC, Campbell AJ. Falling costs: the case for investment. December Falls in people aged 50 and over New Zealand Atlas of Healthcare Variation. Rubenstein LZ.

Falls in older people: epidemiology, risk factors and strategies for prevention. Age Ageing. Robbins AS, Rubenstein LZ, Josephson KR, Schulman BL, Osterweil D, Fine G.

Predictors of falls among elderly people. Results of two population-based studies. Arch Intern Med. Rubenstein LZ, Josephson KR. The epidemiology of falls and syncope. Clin Geriatr Med.

Schlussel MM, dos Anjos LA, de Vasconcellos MT, Kac G. Reference values of handgrip dynamometry of healthy adults: a population-based study. Clin Nutr. Gallagher D, Ruts E, Visser M, Heshka S, Baumgartner RN, Wang J, et al. Weight stability masks sarcopenia in elderly men and women.

Am J Physiol Endocrinol Metab. Goodpaster BH, Park SW, Harris TB, Kritchevsky SB, Nevitt M, Schwartz AV, et al. The loss of skeletal muscle strength, mass, and quality in older adults: the health, aging and body composition study.

J Gerontol A Biol Sci Med Sci. Chen L, Nelson DR, Zhao Y, Cui Z, Johnston JA. Relationship between muscle mass and muscle strength, and the impact of comorbidities: a population-based, cross-sectional study of older adults in the United States.

BMC Geriatr. pmid; PubMed Central PMCID: PMC Reed RL, Pearlmutter L, Yochum K, Meredith KE, Mooradian AD. The relationship between muscle mass and muscle strength in the elderly. J Am Geriatr Soc. Hayashida I, Tanimoto Y, Takahashi Y, Kusabiraki T, Tamaki J.

Correlation between muscle strength and muscle mass, and their association with walking speed, in community-dwelling elderly Japanese individuals.

PLoS One. Hughes VA, Frontera WR, Wood M, Evans WJ, Dallal GE, Roubenoff R, et al. Longitudinal muscle strength changes in older adults: influence of muscle mass, physical activity, and health.

The journals of gerontology Series A, Biological sciences and medical sciences. Ministry of social development. The social Report June Ministry of Health. Wellington: Ministry of Health. Keevil VL, Luben R, Dalzell N, Hayat S, Sayer AA, Wareham NJ, et al. After a 5-min warmup 75 W; bicycle ergo meter—to minimize the chance for injuries , participants were asked to do three sets of 8—10 repetitions on the chest press apparatus and three sets of 8—10 repetitions on the leg press apparatus.

Between each set, there was a 2-min break. Between the leg press and the chest press, there was a 5-min transition time break. Also, the order of the chest press and leg press was randomized to control for a possible order effect. The aerobic exercise protocol conducted on day 2 was based on maximal heart rate and maximal workload measured during the VO 2 max test conducted on day 1, and included both cycling and running.

The running was introduced to also have two different aerobic exercises. Between the three sets of running, participants walked for 1 min. Between the cycling and running, there was a 5-min transition time break. The order of the cycling and running was counterbalanced as well.

Participants completed a questionnaire, based on the reasoned action approach [ 15 ] and the self-determination theory [ 16 ]. This questionnaire included specific and general questions about resistance and aerobic exercises and was divided accordingly into two sections for completion i.

Filling out the questionnaires took about 3—5 min per stage. The measured constructs are as follows: 1 instrumental attitudes cognitive feelings about exercises , 2 experiential attitudes affective feelings about the exercises , 3 intentions whether the participant intends to do the specific exercise in the near future , 4 intrinsic motivation how fun the exercise is , and 5 a-motivation no motivation to do the specific exercise at all.

All items were rated on a 7-point Likert scale. IBM SPSS statistics and Excel were used to analyze the data see also Additional file 2. Frequencies n , means M , and standard deviations SD were calculated to provide an overall picture of the sample.

Paired sample t -tests were conducted to calculate differences between male and female participants. We tested the direct and indirect associations linking BMI scores with psychological constructs regarding strength exercises using the PROCESS software including the bootstrapping method with bias-corrected confidence estimates see also Fig.

Bootstrapping, a non-parametric sampling procedure, was used to assess the significance of indirect effects. Based on the z score of this difference, p values were estimated [ 19 ]. A total of 68 participants participated in this study BMI ranged from 18 to Female participants had a higher fat mass compared to male participants see Table 2.

Weight and BMI were also highly correlated with the fat-free mass and fat-free mass indices, respectively r values ranging from. Correlational analyses. a Correlations between weight and fat mass and between weight and fat-free mass for male and female participants, separately.

b Correlations between BMI and fat mass index and between BMI and fat-free mass index for male and female participants, separately. c Correlations between fat-free mass and strength measures for male and female participants, separately. There was no direct effect of BMI on attitudes, intention, or motivations p values range from.

Indirect effects of BMI on all psychological outcomes were found via fat-free mass and the combined strength score. No indirect effect from BMI to psychological outcomes was found via strength only.

Model for testing the indirect relations of BMI with psychological outcomes. There was neither an direct effect of BMI on psychological outcomes nor an indirect effect of BMI on psychological outcomes via strength. Limited indirect effects of BMI on psychological outcomes were found via fat-free mass.

Significant effects of BMI on psychological outcomes were found when fat-free mass and strength were added to the model. To examine whether heavier people are relatively better in strength exercises than aerobic exercises compared to normal-weight people, correlations between BMI and strength outcomes and BMI and aerobic outcomes were calculated.

For the variables instrumental attitude, experiential attitude, and intention, the directions of the relations were the same, but these variables were not significant p values ranged from.

We 1 confirmed that heavier people have a higher fat-free mass compared to normal-weight people. This is in line with biological insights [ 7 ]. Additionally, 2 we have shown that people with a higher fat-free mass are stronger in absolute sense and are better in strength exercises than in aerobic exercises.

We have also confirmed that 3 mastery experiences in this case, resulting from successfully engaging in strength exercises as opposed to aerobic exercises are related to more positive psychological outcomes. This observation is in line with psychological insights [ 20 , 21 , 22 , 23 ].

As hypothesized, we 4 have shown that heavier people are more positive about strength exercises compared to normal-weight people, via fat-free mass and muscle strength.

Moreover, 5 heavier people are better in strength exercises and are more positive about strength exercises compared to aerobic exercises.

To the best of our knowledge, this is the first time that this chain of relationships has been demonstrated empirically, thereby bridging the gap between biological and psychological insights.

In light of these results, new exercise interventions for people with overweight or obesity could be developed, concentrating on biological strengths and using psychological principles and techniques to make them more aware of their strengths [ 6 ].

Additionally, for long-term behavior and health changes, new interventions might benefit from focusing and giving feedback; [ 24 ] on body composition instead of weight.

There are some limitations that should nuance the drawn conclusions. Most of the study participants are university students who volunteered to participate which might limit the generalizability of our study results.

The self-reported physical activity level was higher than year-old parents 2. The sample size is relatively small, but the used measures were accurate.

The BMI range was limited, making more research necessary among a broader BMI range. Cross-sectional data instead of longitudinal data was gathered. With that, we were not able to show causality.

Two additional questions might be 1 whether the exercise protocols adequately encompass what strength and aerobic exercises are and 2 whether the possibly different training loads of the two different exercises might have influenced the results. To ensure that we actually worked with strength and aerobic exercises, we used exercises that are generally used in our gold standard maximal strength tests and aerobic tests the additional running is also used very often in VO 2 max tests; see, e.

In future research, it might be helpful to add an effort perception scale to measure the perceived intensity of the protocols. However, most of our results were significant and in the right direction.

However, an increased weight or BMI is not a very reliable tool to evaluate body composition and, with that, individual metabolic health [ 27 ]. In conclusion, a benefit of being overweight is being strong. Strength exercise interventions might have the ability to make people who are overweight more motivated to be physically active on the long term.

In short, strength exercises might contribute to the management of obesity. With interventions focusing on strength exercises, the obesity problem per se will not be solved, but such programs might positively contribute to obesity-related health issues.

Alberga AS, Farnesi BC, Lafleche A, Legault L, Komorowski J. The effects of resistance exercise training on body composition and strength in obese prepubertal children.

Physician and Sports Medicine. Article Google Scholar. Swinburn BA, Sacks G, Hall KD, McPherson K, Finegood DT, Moodie ML, Gortmaker SL.

The global obesity pandemic: shaped by global drivers and local environments. Article PubMed Google Scholar. Heath GW, Parra DC, Sarmiento OL, Andersen LB, Owen N, Goenka S, et al. Evidence-based intervention in physical activity: lessons from around the world. Article PubMed PubMed Central Google Scholar.

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A new direction in psychology and health: resistance exercise training for obese children and adolescents. Psychol Health. Ten Hoor GA, Kok G, Rutten GM, Ruiter RAC, Kremers SPJ, Schols AMJW, et al.

BMC Public Health. Article CAS PubMed PubMed Central Google Scholar. Westerterp KR, Donkers JHHLM, Fredrix EWHM, Boekhoudt P. Energy intake, physical activity and body weight: a simulation model. Br J Nutr. Article CAS PubMed Google Scholar. Faigenbaum AD, Kraemer WJ, Blimkie, et al.

Youth resistance training: updated position statement paper from the national strength and conditioning association. J Strength Cond Res. Peters GJY, Abraham C, Crutzen R. Full disclosure: doing behavioural science necessitates sharing. European Health Psychologist. Google Scholar.

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In: Brozek J, Henschel A, editors. Techniques for measuring body composition. Washington, DC: National Academy of Sciences, National Research Council; Kuipers H, Verstappen FT, Keizer HA, Geurten P, van Kranenburg G.

Variability of aerobic performance in the laboratory and its physiologic correlates. Int J Sports Med. Mayhew JL, Prinster JL, Ware JS, Zimmer DL, Arabas JR, Bemben MG. Muscular endurance repetitions to predict bench press strength in men of different training levels.

J Sports Med Phys Fitness. CAS PubMed Google Scholar. Verdijk LB, van Loon L, Meijer K, Savelberg HH. One-repetition maximum strength test represents a valid means to assess leg strength in vivo in humans. J Sports Sci. Fishbein M, Ajzen I. Predicting and changing behavior: the reasoned action approach.

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Morrisville: Lulu. com; Bandura A. Social foundations of thought and action: a social cognitive theory. Englewood Cliffs: Prentice-Hall, Inc. Kelder S, Hoelscher D, Perry CL. How individuals, environments, and health behaviour interact: social cognitive theory.

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Impact of a strength training exercise program on body composition and cardiovascular risk factors in a group of obese schoolchildren by pubertal stage.

American Journal of Sports Science and Medicine.

Descriptive statistics were reported as means ± SD for parametric data, and frequencies and percentages for categorical data. Differences between groups were analysed using independent t-tests for parametric data, and the chi-square test of independence for categorical data.

The measurements were categorized into two groups according to sex. The measurements were further categorized according to body fat percentage into two groups. A multiple linear regression analysis was performed to determine body composition parameters predicting muscle strength in males and females.

Adjusted r, standard error values, and multicollinearity statistics were used to identify the most appropriate equations. This analysis was undertaken in males and females according to obesity classifications based on body fat percentage.

All statistical analyses were completed using the statistical software IBM SPSS version Descriptive statistics for the study population according to sex are presented in Table 1.

The mean ± SD age of participants was Males were taller, heavier and had a lower body fat percentage than females, but these differences were not significant. The mean BMI for this study population fell in the overweight BMI category Using BMI categories, In males and females, 9.

The prevalence of low muscle mass was 2. Appendicular skeletal muscle mass index and muscle strength were higher in males compared with females, this difference was significant for muscle strength only Table 1.

When exploring the association between muscle strength and muscle mass according to obesity classification using body fat percentage, muscle mass was significantly associated with muscle strength in non-obese males and females.

However, in participants with obesity, muscle mass was no longer associated with muscle strength Tables 4 and 5. In this cross-sectional study, we evaluated the relationship between muscle strength, muscle mass, and body fat percentage in older adults living in Auckland, NZ.

The findings indicate that muscle strength was associated with muscle mass. The magnitude of this association was greater in males than females, with addition of body fat percentage slightly increasing the ability of the model to predict muscle strength.

When exploring the association between muscle strength and muscle mass according to obesity classification using body fat percentage, muscle mass was associated with muscle strength in non-obese participants.

However, this association was not observed in older adults who were classified as obese. This indicates that body fat percentage should be considered when measuring associations between muscle mass and muscle strength in older adults.

We found a higher prevalence of participants with obesity using body fat percentage classifications This result was as expected, as BMI has been shown to underestimate adiposity in older adults [ 37 ].

A recent survey in New Zealand using BMI classifications reported that the prevalence of obesity in older adults between 65—74 years was The lower level of obesity reported in our population may reflect our recruitment inadvertently targeting healthy older adults.

We also identified 3. The lack of studies reporting the prevalence of low muscle strength and the application of different cut-off values makes it difficult to compare studies. In this cohort, we applied the updated cut off values of low muscle strength defined by the European Working Group on Sarcopenia in Older People EWGSOP2.

A nationally representative sample of Brazilians aged 65 years and older using the same cut-off values as our study observed a higher prevalence of low muscle strength Other studies which applied the older cut off values defined by the European Working Group on Sarcopenia in Older People EWGSOP , observed a higher prevalence of low muscle strength of The higher prevalence observed in these groups, is possibly explained by the inclusion of people older than 74 years, and a potentially less healthy population than those participants included in our study.

The prevalence of low ASMI was 6. The higher percentage in the study appears to be explained by the inclusion of adults over the ages of 74 years.

Our results provide evidence that muscle mass is positively associated with muscle strength in older men and women. This result aligns with the literature [ 43 , 44 ] and suggests that efforts to maintain muscle mass should have a significant effect on preserving strength in older adults.

When stratified by sex, we observed strong evidence that muscle mass was significantly associated, but not a major contributor to muscle strength in older men and women. In a regression model taking into account muscle mass, it was shown that an increase of 1 unit muscle mass will increase the value of muscle strength by 0.

These results highlight not only the importance of increasing muscle mass, but also the importance of decreasing body fat percentage to preserve muscle strength in older adults. The cross-sectional nature of our data impedes any causal inference.

Nevertheless, the results from our study provide justification for further prospective research that evaluates the effects of interventions, which are aimed at optimising body composition and muscle strength in older adults.

To our knowledge, this is the first study to investigate the role of obesity classification based on body fat percentage in the relationship between muscle strength and muscle mass.

Results from multiple linear regression analyses provide evidence supporting the important role of obesity classification according to body fat percentage when investigating the relationship between muscle strength and muscle mass.

Our study demonstrated that when obesity was classified using body fat percentage, muscle mass was significantly associated with muscle strength in non-obese older adults. However, an association between muscle strength and muscle mass was not observed in older adults categorised as obese.

The accumulation of intramuscular lipid content or poor muscle quality , which is seen in people with obesity may explain the influence of obesity in the relationship between muscle strength and muscle mass.

Goodpaster et al. reported that higher intramuscular lipid content is associated with lower muscle strength, independent of muscle mass [ 45 ]. Also, accumulation of intramuscular lipid content is known to be associated with insulin insensitivity, inflammation and functional deficits in skeletal muscle.

It will be important in the future to continue to focus on understanding predictors of muscle strength in older adults with obesity in order to provide appropriate interventions to increase muscle strength.

There were significant strengths to our study. The relatively large sample size permits us to examine whether the relationship between muscle strength and muscle mass was similar in males and females. Also, it is possible that the inclusion of community-dwelling healthy older adults provides the opportunity to identify issues and promote preventative action in early old age.

Furthermore, the use of DXA is an accurate measure of body composition. However, in contrast to magnetic resonance imaging MRI or computed tomography CT DXA cannot detect intramuscular fat from muscle mass nor distinguish the composition of muscle [ 46 , 47 ].

This cross-sectional study limits the ability to detect causality; hence, only associations were discussed. Other limitations are the population group, which was not representative of the New Zealand population, as this cohort was composed of a convenience volunteer sample of men and women aged 65—74 years living in the community.

The classification by body fat percentage for obesity may also be perceived as a limitation given the arbitrary nature of the cut-off points. Finally, we did not assess lower extremity muscle strength, which is a more direct predictor of falls. However, grip strength is associated with lower-body muscle strength [ 48 ] and a strong predictor of disability [ 49 ].

Muscle mass and body fat percentage were predictors of muscle strength in this cohort. Muscle mass was associated with muscle strength in non-obese older adults whereas, there was no association between muscle mass and muscle strength in older adults who were classified as obese.

This indicates that obesity classification plays an important role in the relationship between muscle strength and muscle mass in older adults. We suggest that this could be mainly attributed to muscle quality, which could be a contributor of muscle strength in older adults who are obese.

Further research should focus on identifying predictors of muscle strength in older adults with obesity. We thank the REACH team including Cassie Slade for managing the recruitment of participants and data collection; and Karen Mumme, Harriet Guy, Angela Yu, and Nicola Gillies for assistance with data collection and data entry.

Browse Subject Areas? Click through the PLOS taxonomy to find articles in your field. Article Authors Metrics Comments Media Coverage Reader Comments Figures. Abstract Background Aging is associated with decreases in muscle strength and simultaneous changes in body composition, including decreases in muscle mass, muscle quality and increases in adiposity.

Conclusions Body fat percentage should be considered when measuring associations between muscle mass and muscle strength in older adults. Introduction Globally and in New Zealand the proportion of older adults is increasing [ 1 ]. Materials and methods 2. Study design This study was a secondary aim of the Researching Eating, Activity and Cognitive Health REACH Study.

Study participants and procedures Participants included men and women aged 65—74 years, living independently in Auckland, NZ. Data collection All participants visited the Human Nutrition Research Unit on one occasion for collection of data as part of the wider REACH study.

Statistical analysis Continuous data were assessed for normality using Shapiro Wilcoxon tests and visual assessment of histograms. Download: PPT.

Table 1. Characteristics of study participants by sex a , b. Fig 1. Table 2. Results of multiple linear regression modelling on the relationship between muscle strength, mass and body fat percentage in older females.

Table 3. Results of multiple linear regression modelling on the relationship between muscle strength, mass and body fat percentage in older males. Table 4. Results of multiple linear regression modelling on the effect of obesity in the relationship between muscle strength and mass in older females.

Table 5. Results of multiple linear regression modelling on the effect of obesity in the relationship between muscle strength and mass in older males. Discussion In this cross-sectional study, we evaluated the relationship between muscle strength, muscle mass, and body fat percentage in older adults living in Auckland, NZ.

Prevalence of obesity, low muscle strength and low muscle mass We found a higher prevalence of participants with obesity using body fat percentage classifications Association between body composition and muscle strength Our results provide evidence that muscle mass is positively associated with muscle strength in older men and women.

The role of obesity classification in the relationship between muscle strength and muscle mass To our knowledge, this is the first study to investigate the role of obesity classification based on body fat percentage in the relationship between muscle strength and muscle mass.

Conclusions Muscle mass and body fat percentage were predictors of muscle strength in this cohort. Supporting information.

S1 File. s SAV. Acknowledgments We thank the REACH team including Cassie Slade for managing the recruitment of participants and data collection; and Karen Mumme, Harriet Guy, Angela Yu, and Nicola Gillies for assistance with data collection and data entry.

References 1. United Nations, Department of Economic and Social Affairs, Population Division. Statistics New Zealand. A statistical volume, Wellington. Robertson MC, Campbell AJ.

Falling costs: the case for investment. December Falls in people aged 50 and over New Zealand Atlas of Healthcare Variation. Rubenstein LZ. Falls in older people: epidemiology, risk factors and strategies for prevention. Age Ageing.

Robbins AS, Rubenstein LZ, Josephson KR, Schulman BL, Osterweil D, Fine G. Predictors of falls among elderly people. Results of two population-based studies. Arch Intern Med. Rubenstein LZ, Josephson KR. The epidemiology of falls and syncope. Clin Geriatr Med. Schlussel MM, dos Anjos LA, de Vasconcellos MT, Kac G.

Reference values of handgrip dynamometry of healthy adults: a population-based study. Clin Nutr. Gallagher D, Ruts E, Visser M, Heshka S, Baumgartner RN, Wang J, et al. Weight stability masks sarcopenia in elderly men and women. Am J Physiol Endocrinol Metab. Goodpaster BH, Park SW, Harris TB, Kritchevsky SB, Nevitt M, Schwartz AV, et al.

The loss of skeletal muscle strength, mass, and quality in older adults: the health, aging and body composition study. J Gerontol A Biol Sci Med Sci. Chen L, Nelson DR, Zhao Y, Cui Z, Johnston JA.

Relationship between muscle mass and muscle strength, and the impact of comorbidities: a population-based, cross-sectional study of older adults in the United States. BMC Geriatr. pmid; PubMed Central PMCID: PMC Reed RL, Pearlmutter L, Yochum K, Meredith KE, Mooradian AD.

The relationship between muscle mass and muscle strength in the elderly. J Am Geriatr Soc. Hayashida I, Tanimoto Y, Takahashi Y, Kusabiraki T, Tamaki J.

Correlation between muscle strength and muscle mass, and their association with walking speed, in community-dwelling elderly Japanese individuals. PLoS One. Hughes VA, Frontera WR, Wood M, Evans WJ, Dallal GE, Roubenoff R, et al.

Longitudinal muscle strength changes in older adults: influence of muscle mass, physical activity, and health. The journals of gerontology Series A, Biological sciences and medical sciences.

Ministry of social development. The social Report June Ministry of Health. Wellington: Ministry of Health. Keevil VL, Luben R, Dalzell N, Hayat S, Sayer AA, Wareham NJ, et al. Cross-sectional associations between different measures of obesity and muscle strength in men and women in a British cohort study.

J Nutr Health Aging. Borges VS, Lima-Costa MFF, Andrade FB. Other benefits are noticeable after a few months, like increased muscle mass, strength, flexibility, and lung capacity 1. Further, numerous studies have found that being physically fit protects against many diseases and health issues — including heart disease, stroke, type 2 diabetes, osteoporosis, depression, dementia, and certain types of cancer, just to name a few 1 , 3 , 4 , 5 , 6 , 7.

Being physically active can also support healthy aging and increase how many healthy, active years you have. For example, strength training into late adulthood can help preserve lean muscle mass, which is a major predictor of falls and quality of life 1 , 8 , 9.

Ultimately, living an active lifestyle no matter your age is important for supporting good overall health. A well-rounded exercise program has been shown to improve your health in many areas.

For instance, it can reduce the risk of chronic disease, improve your mental wellbeing, and support healthy aging. Good cardio fitness allows you to perform different activities for longer because your heart and lungs are able to deliver oxygen and nutrients to your working muscles.

Examples of activities that benefit from good cardio endurance include walking, jogging, swimming, cycling, and other sports that require continuous movement. Moderate-intensity exercise can be sustained for longer than vigorous-intensity exercise, though exactly how long varies between individuals and their fitness levels 1.

What is moderate intensity for one person may be vigorous for another. If you become fatigued or out of breath quickly, decrease the intensity or duration of your exercise and build up from there.

Any increase in cardio exercise is beneficial, so make realistic goals that work best for you. Cardiovascular endurance, or cardio, is important for strengthening your heart and lungs, which help to deliver oxygen and nutrients throughout your body.

Muscular strength is the ability of a muscle group to exert force or lift and carry weight. The stronger your muscles, the heavier weight you can lift and move Muscular strength can vary between different muscle groups.

For example, you may have strong glutes and quads but weaker biceps. To measure your muscular strength, you can test your one-rep max, which is the maximum weight you can lift for one rep.

Progressive overload — defined as gradually increasing weight, volume, training frequency, or intensity over time — is another great way to measure your progress In addition to building strength, you may want to aim for muscle hypertrophy, or building muscle mass.

To do so, aim for 8—12 reps per set. If you want to increase your one-rep max, focus on your maximal muscular strength. You can do so by incorporating exercises with heavy weights and low reps — usually 2—6.

Make sure you practice proper form to reduce the risk of injury 10 , Being physically strong helps you move and lift heavier objects with ease, which can make day-to-day tasks much easier.

Unlike muscular strength, which measures how much weight you can lift or move, muscular endurance tests how long your muscles can withstand an exercise In addition to training for muscular strength, make sure you add some muscular endurance activities into your routine, such as:.

For example, pilates, yoga, stair climbing, and long-distance activities are good options. Muscular endurance is how long your muscles can endure an exercise.

Flexibility is defined as the range of motion of a joint or group of joints without pain or difficulty 1. Being flexible is important for daily living. For instance, it can make it easier to maintain good balance, reach the top shelf of a cupboard, or bend down to pick up something from the ground.

Further, some activities require more flexibility than others, such as gymnastics, dance, and martial arts. Though there is debate on its benefits in reducing pain and injury risk, stretching can increase your flexibility and may enhance your performance in activities that require you to be more flexible 13 , When stretching, the goal is to be gentle and limit the risk of injury.

Avoid stretching your muscles to the point of extreme discomfort or pain. Aim to do stretching activities at least 2—3 days per week. While helpful for flexibility, it may increase the risk of injury prior to activities that rely on joint support, such as weight training or high intensity sports. Therefore, this type of stretching is generally best reserved for the cool-down phase of a workout.

This is usually done during a warm-up or can be done by itself like during a stretching break at work. These include exercises that elongate and stretch the muscle during movements, such as when performing pilates, yoga, tai chi, and barre.

The purpose of dynamic movement is to wake up the muscles needed for the upcoming exercise. Endurance exercises that benefit from dynamic movement include biking, running, and swimming, as well as sports activities like basketball, soccer, and volleyball. Regular stretching can help increase flexibility and may support your performance in sports that require flexibility.

Being flexible may help you perform daily tasks easier and maintain better balance, though more research is needed. Body composition is the last health-related component of fitness. It describes the ratio of fat mass to fat-free mass 2. Body fat is essential to human health.

However, having too much — especially around the stomach area — has been linked to poorer health and a greater risk of chronic diseases like heart disease, type 2 diabetes, and certain types of cancer 15 , Meanwhile, having greater muscle and bone mass is linked with improved health outcomes and a lower risk of chronic diseases Keep in mind that health looks different for everyone.

The below parameters can help you understand your body composition 18 , 19 , 20 , 21 :. You can also use body mass index BMI to give you a general idea of your body composition.

Focusing on the other four areas of fitness — cardiovascular endurance, flexibility, and muscular strength and endurance — may help you achieve a healthy body composition.

While every body is different, having too much body fat and not enough muscle can lead to health problems. Fortunately, the other four components of fitness can help you achieve a body composition that is healthy for you. Ideally, aim to reach the physical activity guidelines, which include 1 :.

You can assign each component to certain days of the week or incorporate each aspect into a single workout. For example, you may choose to do strength training on Monday, Wednesday, and Friday, cardio on Tuesday, Thursday, and Saturday, and stretching a few days a week. Alternatively, you can focus on exercises that incorporate both strength training and cardio, such as high intensity interval training or boot camps.

Ultimately, the goal is to add each component of fitness into your training program in a way that works for you. For a well-rounded exercise program, try to incorporate the first four components of fitness — cardio, muscular strength and endurance, and flexibility — into your training plan throughout the week.

Sci Rep. Barber TM, Hanson P, Weickert MO, Franks S. Obesity and polycystic ovary syndrome: implications for pathogenesis and novel management strategies.

Clin Med Insights Reprod Health. Cardoos N. Overtraining syndrome. Curr Sports Med Reports. National Academy of Sports Medicine. Exploring the science of muscle recovery. Bellicha A, Baak MA, Battista F, et al. Effect of exercise training on weight loss, body composition changes, and weight maintenance in adults with overweight or obesity: An overview of 12 systematic reviews and studies.

Obesity Reviews. Slater GJ, Dieter BP, Marsh DJ, Helms ER, Shaw G, Iraki J. Is an energy surplus required to maximize skeletal muscle hypertrophy associated with resistance training.

Front Nutr. Schoenfeld BJ, Ogborn D, Krieger JW. Effects of resistance training frequency on measures of muscle hypertrophy: a systematic review and meta-analysis. Sports Med. Schoenfeld BJ, Contreras B, Krieger J, et al. Resistance training volume enhances muscle hypertrophy but not strength in trained men.

By Rachel MacPherson, BA, CPT Rachel MacPherson is a health writer, certified personal trainer, and exercise nutrition coach based in Halifax. Use limited data to select advertising. Create profiles for personalised advertising.

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Measure content performance. Understand audiences through statistics or combinations of data from different sources. Develop and improve services. Use limited data to select content. List of Partners vendors. By Rachel MacPherson is a health writer, certified personal trainer, certified strength and conditioning specialist, and exercise nutrition coach based in Halifax.

Rachel MacPherson, BA, CPT. Learn about our editorial process. Learn more. Medical Reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates.

Medically reviewed by Barbie Cervoni MS, RD, CDCES, CDN. Learn about our Medical Review Board. Table of Contents View All. Table of Contents. What Is Body Composition? How Do You Improve Body Composition? Exercises That Could Impact Body Composition. Building Body Composition Workouts.

How to Prevent Muscle Loss. What You Need to Know About Bulking. Aerobic exercise HIIT training Weight lifting Bodyweight training Walking Daily activities house cleaning, gardening, etc. A Fundamental Guide to Weight Training. How to Sit Less: Everyday Hacks to Increase Your Daily Movement.

The Reason Athletes Eat White Rice Instead of Brown. Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

S Chang CS, Liu IT, Liang FW, et al. See Our Editorial Process. The five health-related components of physical fitness are cardiovascular endurance, muscular strength, muscular endurance, flexibility, and body composition. Some benefits are immediate, like improved mood, sleep, insulin sensitivity, and blood pressure.

Other benefits are noticeable after a few months, like increased muscle mass, strength, flexibility, and lung capacity 1. Further, numerous studies have found that being physically fit protects against many diseases and health issues — including heart disease, stroke, type 2 diabetes, osteoporosis, depression, dementia, and certain types of cancer, just to name a few 1 , 3 , 4 , 5 , 6 , 7.

Being physically active can also support healthy aging and increase how many healthy, active years you have. For example, strength training into late adulthood can help preserve lean muscle mass, which is a major predictor of falls and quality of life 1 , 8 , 9.

Ultimately, living an active lifestyle no matter your age is important for supporting good overall health. A well-rounded exercise program has been shown to improve your health in many areas.

For instance, it can reduce the risk of chronic disease, improve your mental wellbeing, and support healthy aging. Good cardio fitness allows you to perform different activities for longer because your heart and lungs are able to deliver oxygen and nutrients to your working muscles.

Examples of activities that benefit from good cardio endurance include walking, jogging, swimming, cycling, and other sports that require continuous movement. Moderate-intensity exercise can be sustained for longer than vigorous-intensity exercise, though exactly how long varies between individuals and their fitness levels 1.

What is moderate intensity for one person may be vigorous for another. If you become fatigued or out of breath quickly, decrease the intensity or duration of your exercise and build up from there.

Any increase in cardio exercise is beneficial, so make realistic goals that work best for you. Cardiovascular endurance, or cardio, is important for strengthening your heart and lungs, which help to deliver oxygen and nutrients throughout your body.

Muscular strength is the ability of a muscle group to exert force or lift and carry weight. The stronger your muscles, the heavier weight you can lift and move Muscular strength can vary between different muscle groups.

For example, you may have strong glutes and quads but weaker biceps. To measure your muscular strength, you can test your one-rep max, which is the maximum weight you can lift for one rep.

Progressive overload — defined as gradually increasing weight, volume, training frequency, or intensity over time — is another great way to measure your progress In addition to building strength, you may want to aim for muscle hypertrophy, or building muscle mass. To do so, aim for 8—12 reps per set.

If you want to increase your one-rep max, focus on your maximal muscular strength. You can do so by incorporating exercises with heavy weights and low reps — usually 2—6.

Make sure you practice proper form to reduce the risk of injury 10 , Being physically strong helps you move and lift heavier objects with ease, which can make day-to-day tasks much easier.

Unlike muscular strength, which measures how much weight you can lift or move, muscular endurance tests how long your muscles can withstand an exercise In addition to training for muscular strength, make sure you add some muscular endurance activities into your routine, such as:.

For example, pilates, yoga, stair climbing, and long-distance activities are good options. Muscular endurance is how long your muscles can endure an exercise.

Flexibility is defined as the range of motion of a joint or group of joints without pain or difficulty 1. Being flexible is important for daily living. For instance, it can make it easier to maintain good balance, reach the top shelf of a cupboard, or bend down to pick up something from the ground.

Further, some activities require more flexibility than others, such as gymnastics, dance, and martial arts. Though there is debate on its benefits in reducing pain and injury risk, stretching can increase your flexibility and may enhance your performance in activities that require you to be more flexible 13 , When stretching, the goal is to be gentle and limit the risk of injury.

Avoid stretching your muscles to the point of extreme discomfort or pain. Aim to do stretching activities at least 2—3 days per week.

While helpful for flexibility, it may increase the risk of injury prior to activities that rely on joint support, such as weight training or high intensity sports. Therefore, this type of stretching is generally best reserved for the cool-down phase of a workout.

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Download references. The authors thank Margreet Meems, Lena Lütgehetmann, and Gulsen Kadri for their help during the measurements, and Robert Ruiter and Rik Crutzen for their critical review of the final manuscript. This study is funded by the Netherlands Organization for Health Research and Development ZonMw; project number All research materials and data are combined in a.

zip archive labeled Additional file 1. Box , MD, Maastricht, The Netherlands. Department of Work and Social Psychology, Maastricht University, P. Department of Respiratory Medicine, Research School NUTRIM, Maastricht University Medical Centre, P.

You can also search for this author in PubMed Google Scholar. GtH, GP, AS, and GK conceived of, designed, and coordinated the study. GtH and GP performed the analyses. GtH drafted the manuscript. All authors read and approved the final manuscript.

Correspondence to Gill A. ten Hoor. All authors Gill A.