This helps you play your sport with less effort and for a longer period. Strength training and flexibility exercises work together to create a more effective driving action. This advantage is especially clear in baseball, golf, tennis, and other sports that involve brief, explosive action.

You'll see a measurable improvement in both force and range. The best strategy is to condition all of your muscles, no matter what your sport. Otherwise, the muscles you ignore become weak and can be easily injured. In addition, for peak performance, focus on those muscles emphasized in your sport.

Here are some conditioning strategies for some popular spring sports:. This sport has a high risk of injury. This is because players who stand around in the outfield suddenly have to dive for the ball or sprint. You should have very flexible hamstrings and have strong, well-balanced leg muscles.

You also need to condition the back, shoulder, and elbow muscles, which support throwing and batting. A golf swing puts tough demands on lower-back muscles, especially when the back is out of condition. Sprouts are easy to prepare and digest.

Plus, they can help your body neutralize free radicals to create a more alkaline environment for proper cell functioning. Chronic inflammation in the body can lead to serious illness if left untreated.

Inflammation can lead to:. Omega-3 fatty acids can reduce this inflammation and support many processes that contribute to cellular healing.

Flaxseed is high in omega-3s and dietary fiber. It may also help lower cholesterol levels. Other great omega-3 sources are chia seeds and walnuts. Beets are high in carbohydrates needed for sustained energy and contain many antioxidant and anti-inflammatory nutrients.

The high nitrate content of beets may also help dilate blood vessels. This can help lower blood pressure and increase the amount of oxygen delivered to the cells.

Drinking a cup of beetroot juice a day may help lower blood pressure and aid blood flow, according to a study reported by the American Heart Association. If you are in good general health, but often find yourself out of breath or having difficulty controlling your heart rate during exercise, your body may be running low on iron.

Iron is essential in the production of healthy red blood cells that deliver oxygen to tissues in the body. Without enough iron in the blood, you become fatigued faster.

The lack of oxygenation can affect your heart rate and immune function. Squash and pumpkin seeds are a great source of plant-based iron. Intense exercise can be hard on your body. Proper recovery is essential to improving your strength. Healthy fats and foods rich in essential vitamins and minerals can help improve immune and thyroid function.

They can also protect and repair bones and connective tissue. Brazil nuts are an excellent source of proteins, fats, and other essential nutrients. According to the Mayo Clinic , Brazil nuts are high in nutrients that help control blood pressure, such as:.

Eating just a few Brazil nuts each day can stimulate your natural recovery processes and help you build and maintain strong bones and muscles. This supports the notion that endurance athletes with longer races may benefit most from caffeine for performance enhancement since they have the greatest likelihood of being fatigued.

This also supports findings in other investigations that show ingesting caffeine at various time points including late in exercise may be most beneficial [ ]. For example, an early study [ ] aimed to understand whether or not there were benefits to a common practice among endurance athletes, such as those participating in marathons and triathlons, which is to drink flat cola toward the end of an event.

When researchers investigated the ingestion of a low dose of caffeine toward the end of a race e. The study also demonstrated that the effect was due to the caffeine and not the carbohydrate, which may also aid performance as fuel stores become depleted [ ]. This may have been due to the faster absorption with caffeinated gum consumption, and due to the continued increase in plasma caffeine concentrations during the cycling time trial, when athletes may become fatigued i.

However, there was significant interindividual variability, highlighting the need for athletes to experiment with their own strategies as far as dosing and timing are concerned.

The optimal timing of caffeine ingestion may depend on the source of caffeine. As stated earlier, some of the alternate sources of caffeine such as caffeine chewing gums may absorb more quickly than caffeine ingested in caffeine-containing capsules [ 60 ]. Therefore, individuals interested in supplementing with caffeine should consider that timing of caffeine ingestion will likely be influenced by the source of caffeine.

Currently, only a few investigations [ 96 , , , , , ] have included both trained and untrained subjects in their study design. A limitation of this study is that the swimming exercise task differed between the trained and untrained participants. Specifically, the study utilized m swimming for the trained swimmers and m for the untrained swimmers, which is a likely explanation for these findings.

However, some have also postulated that this is because athletes perform more reliably on a given task than nonathletes, and increased test-retest reliability might prevent type II errors [ ]. In contrast to the above evidence regarding the importance of training status, other research has shown that training status does not moderate the ergogenic effects of caffeine on exercise performance.

One study [ ] showed similar performance improvements 1. Similarly, Astorino et al. More recently, a small study by Boyett et al. Subjects completed four experimental trials consisting of a 3-km cycling time trial performed in randomized order for each combination of time of day morning and evening and treatment.

They reported that both untrained and trained subjects improved performance with caffeine supplementation in the morning; however, only the untrained subjects improved when tested in the evening.

Although there were some limitations to this study, these observations indicate that trained athletes are more likely to experience ergogenic effects from caffeine in the morning, while untrained individuals appear to receive larger gains from caffeine in the evening than their trained counterparts.

This may further complicate the training status data with a possible temporal effect [ ]. The concentration of adenosine receptors the primary target of caffeine do appear to be higher in trained compared to untrained individuals, but this has only been reported in animal studies [ ].

Boyett et al. Although some studies comparing training status of subjects support the notion [ ] that training influences response to caffeine during exercise, most do not [ 96 , , ] and this was also the finding in a subsequent meta-analysis [ ].

It is possible that the only difference between trained and untrained individuals is that trained individuals likely have the mental discipline to exercise long or hard enough to benefit more from the caffeine stimulus, which might provide an explanation for why in some studies, trained individuals respond better to caffeine [ ].

Currently, it seems that trained and untrained individuals experience similar improvements in performance following caffeine ingestion; however, more research in this area is warranted. The impacts of caffeine on sleep and behavior after sleep deprivation are widely reported [ ].

Sleep is recognized as an essential component of physiological and psychological recovery from, and preparation for, high-intensity training in athletes [ , ].

Chronic mild to moderate sleep deprivation in athletes, potentially attributed to caffeine intakes, may result in negative or altered impacts on glucose metabolism, neuroendocrine function, appetite, food intake and protein synthesis, as well as attention, learning and memory [ ].

Objective sleep measures using actigraphy or carried out in laboratory conditions with EEG have shown that caffeine negatively impacts several aspects of sleep quality such as: sleep latency time to fall asleep , WASO wake time after sleep onset , sleep efficiency and duration [ ].

Studies in athletes have also shown adverse effects in sleep quality and markers for exercise recovery after a variety of doses of caffeine ingestion [ , , ]. Although caffeine is associated with sleep disturbances, caffeine has also been shown to improve vigilance and reaction time and improved physical performance after sleep deprivation [ , , , , ].

This may be beneficial for athletes or those in the military who are traveling or involved in multiday operations, or sporting events and must perform at the highest level under sleep-deprived conditions [ , , , ].

Even though caffeine ingestion may hinder sleep quality, the time of day at which caffeine is ingested will likely determine the incidence of these negative effects. For example, in one study that included a sample size of 13 participants, ingestion of caffeine in the morning hours negatively affected sleep only in one participant [ ].

Unfortunately, athletes and those in the military are unlikely to be able to make adjustments to the timing of training, competition and military exercises or the ability to be combat ready. However, to help avoid negative effects on sleep, athletes may consider using caffeine earlier in the day whenever possible.

Pronounced individual differences have also been reported where functional genetic polymorphisms have been implicated in contributing to individual sensitivity to sleep disruption [ , ] and caffeine impacts after sleep deprivation [ ] as discussed in the Interindividual variation in response to caffeine: Genetics section of this paper.

As with any supplement, caffeine ingestion is also associated with certain side-effects. Some of the most commonly reported side-effects in the literature are tachycardia and heart palpitations, anxiety [ , ], headaches, as well as insomnia and hindered sleep quality [ , ].

For example, in one study, caffeine ingestion before an evening Super Rugby game resulted in a delay in time at sleep onset and a reduction in sleep duration on the night of the game [ ].

Caffeine ingestion is also associated with increased anxiety; therefore, its ingestion before competitions in athletes may exacerbate feelings of anxiety and negatively impact overall performance see caffeine and anxiety section. For example, athletes competing in sports that heavily rely on the skill component e.

However, athletes in sports that depend more on physical capabilities, such as strength and endurance e. These aspects are less explored in research but certainly warrant consideration in the practical context to optimize the response to caffeine supplementation.

The primary determinant in the incidence and severity of side-effects associated with caffeine ingestion is the dose used. Side-effects with caffeine seem to increase linearly with the dose ingested [ ].

Therefore, they can be minimized—but likely not fully eliminated—by using smaller doses, as such doses are also found to be ergogenic and produce substantially fewer side-effects [ ]. In summary, an individual case-by-case basis approach is warranted when it comes to caffeine supplementation, as its potential to enhance performance benefit needs to be balanced with the side-effects risk.

In addition to exercise performance, caffeine has also been studied for its contribution to athletes of all types including Special Forces operators in the military who are routinely required to undergo periods of sustained cognitive function and vigilance due to their job requirements Table 1.

Hogervorst et al. They found that caffeine in a carbohydrate-containing performance bar significantly improved both endurance performance and complex cognitive ability during and after exercise [ 82 ]. Antonio et al. This matches a IOM report [ ] that the effects of caffeine supplementation include increased attention and vigilance, complex reaction time, and problem-solving and reasoning.

One confounding factor on cognitive effects of caffeine is the role of sleep. Special Forces military athletes conduct operations where sleep deprivation is common.

A series of different experiments [ 42 , , , , , , , ] have examined the effects of caffeine in real-life military conditions. In three of the studies [ , , ], soldiers performed a series of tasks such as a 4 or 6. The investigators found that vigilance was either maintained or enhanced under the caffeine conditions vs.

placebo , in addition to improvements in run times and obstacle course completion [ , , ]. Similarly, Lieberman et al. Navy Seals. The positive effects of caffeine on cognitive function were further supported by work from Kamimori et al.

The caffeine intervention maintained psychomotor speed, improved event detection, increased the number of correct responses to stimuli, and increased response speed during logical reasoning tests. Under similar conditions of sleep deprivation, Tikuisis et al.

When subjects are not sleep deprived, the effects of caffeine on cognition appear to be less effective. For example, Share et al. In addition to the ability of caffeine to counteract the stress from sleep deprivation, it may also play a role in combatting other stressors.

Gillingham et al. However, these benefits were not observed during more complex operations [ ]. Crowe et al. Again, no cognitive benefit was observed. Other studies [ , , , ] support the effects of caffeine on the cognitive aspects of sport performance, even though with some mixed results [ , ].

Foskett et al. This was supported by Stuart et al. firefighting, military related tasks, wheelchair basketball [ ]. The exact mechanism of how caffeine enhances cognition in relation to exercise is not fully elucidated and appears to work through both peripheral and central neural effects [ ].

In a study by Lieberman et al. Repeated acquisition are behavioral tests in which subjects are required to learn new response sequences within each experimental session [ ]. The researchers [ 42 ] speculated that caffeine exerted its effects from an increased ability to sustain concentration, as opposed to an actual effect on working memory.

Other data [ ] were in agreement that caffeine reduced reaction times via an effect on perceptual-attentional processes not motor processes. This is in direct contrast to earlier work that cited primarily a motor effect [ ].

Another study with a sugar free energy drink showed similar improvements in reaction time in the caffeinated arm; however, they attributed it to parallel changes in cortical excitability at rest, prior, and after a non-fatiguing muscle contraction [ ].

The exact cognitive mechanism s of caffeine have yet to be elucidated. Based on some of the research cited above, it appears that caffeine is an effective ergogenic aid for individuals either involved in special force military units or who may routinely undergo stress including, but not limited to, extended periods of sleep deprivation.

Caffeine in these conditions has been shown to enhance cognitive parameters of concentration and alertness. It has been shown that caffeine may also benefit sport performance via enhanced passing accuracy and agility.

However, not all of the research is in agreement. It is unlikely that caffeine would be more effective than actually sleeping, i. Physical activity and exercise in extreme environments are of great interest as major sporting events e. Tour de France, Leadville , Badwater Ultramarathon are commonly held in extreme environmental conditions.

Events that take place in the heat or at high altitudes bring additional physiological challenges i. Nonetheless, caffeine is widely used by athletes as an ergogenic aid when exercising or performing in extreme environmental situations.

Ely et al. Although caffeine may induce mild fluid loss, the majority of research has confirmed that caffeine consumption does not significantly impair hydration status, exacerbate dehydration, or jeopardize thermoregulation i. Several trials have observed no benefit of acute caffeine ingestion on cycling and running performance in the heat Table 2 [ , , ].

It is well established that caffeine improves performance and perceived exertion during exercise at sea level [ , , , ]. Despite positive outcomes at sea level, minimal data exist on the ergogenic effects or side effects of caffeine in conditions of hypoxia, likely due to accessibility of this environment or the prohibitive costs of artificial methods.

To date, only four investigations Table 3 have examined the effects of caffeine on exercise performance under hypoxic conditions [ , , , ]. Overall, results to date appear to support the beneficial effects of caffeine supplementation that may partly reduce the negative effects of hypoxia on the perception of effort and endurance performance [ , , , ].

Sources other than commonly consumed coffee and caffeine tablets have garnered interest, including caffeinated chewing gum, mouth rinses, aerosols, inspired powders, energy bars, energy gels and chews, among others.

While the pharmacokinetics [ 18 , , , , ] and effects of caffeine on performance when consumed in a traditional manner, such as coffee [ 47 , 49 , 55 , , , , ] or as a caffeine capsule with fluid [ 55 , , , ] are well understood, curiosity in alternate forms of delivery as outlined in pharmacokinetics section have emerged due to interest in the speed of delivery [ 81 ].

A recent review by Wickham and Spriet [ 5 ] provides an overview of the literature pertaining to caffeine use in exercise, in alternate forms. Therefore, here we only briefly summarize the current research.

Several investigations have suggested that delivering caffeine in chewing gum form may speed the rate of caffeine delivery to the blood via absorption through the extremely vascular buccal cavity [ 58 , ].

Kamimori and colleagues [ 58 ] compared the rate of absorption and relative caffeine bioavailability from caffeinated chewing gum and caffeine in capsule form. The results suggest that the rate of drug absorption from the gum formulation was significantly faster. These findings suggest that there may be an earlier onset of pharmacological effects from caffeine delivered through the gum formulation.

Further, while no data exist to date, it has been suggested that increasing absorption via the buccal cavity may be preferential over oral delivery if consumed closer to or during exercise, as splanchnic blood flow is often reduced [ ], potentially slowing the rate of caffeine absorption.

To date, five studies [ 59 , 60 , 61 , 62 , 63 ] have examined the potential ergogenic impact of caffeinated chewing gum on aerobic performance, commonly administered in multiple sticks Table 4.

To note, all studies have been conducted using cycling interventions, with the majority conducted in well-trained cyclists. However, more research is needed, especially in physically active and recreationally training individuals. Four studies [ 64 , 66 , 68 , ] have examined the effect of caffeinated chewing gum on more anaerobic type activities Table 4.

Specifically, Paton et al. The reduced fatigue in the caffeine trials equated to a 5. Caffeinated gum consumption also positively influenced performance in two out of three soccer-specific Yo-Yo Intermittent Recovery Test and CMJ tests used in the assessment of performance in soccer players [ 66 ].

These results suggest that caffeine chewing gums may provide ergogenic effects across a wide range of exercise tasks. To date, only Bellar et al.

Future studies may consider comparing the effects of caffeine in chewing gums to caffeine ingested in capsules. Specifically, the mouth contains bitter taste sensory receptors that are sensitive to caffeine [ ]. It has been proposed that activation of these bitter taste receptors may activate neural pathways associated with information processing and reward within the brain [ , , ].

Physiologically, caffeinated mouth rinsing may also reduce gastrointestinal distress potential that may be caused when ingesting caffeine sources [ , ]. Few investigations on aerobic [ 69 , 74 , 75 , 76 , ] and anaerobic [ 72 , 73 , 78 ] changes in performance, as well as cognitive function [ 70 , 71 ] and performance [ 77 ], following CMR have been conducted to date Table 5.

One study [ ] demonstrated ergogenic benefits of CMR on aerobic performance, reporting significant increases in distance covered during a min arm crank time trial performance.

With regard to anaerobic trials, other researchers [ 72 ] have also observed improved performance, where recreationally active males significantly improved their mean power output during repeated 6-s sprints after rinsing with a 1.

While CMR has demonstrated positive outcomes for cyclists, another study [ 78 ] in recreationally resistance-trained males did not report any significant differences in the total weight lifted by following a 1.

CMR appears to be ergogenic in cycling to include both longer, lower-intensity and shorter high-intensity protocols. The findings on the topic are equivocal likely because caffeine provided in this source does not increase caffeine plasma concentration and increases in plasma concentration are likely needed to experience an ergogenic effect of caffeine [ 69 ].

Details of these studies, as well as additional studies may be found in Table 5. The use of caffeinated nasal sprays and inspired powders are also of interest. Three mechanisms of action have been hypothesized for caffeinated nasal sprays.

Firstly, the nasal mucosa is permeable, making the nasal cavity a potential route for local and systemic substance delivery; particularly for caffeine, a small molecular compound [ 11 , 12 , 30 , 31 ].

Secondly, and similar to CMR, bitter taste receptors are located in the nasal cavity. The use of a nasal spray may allow for the upregulation of brain activity associated with reward and information processing [ ]. Thirdly, but often questioned due to its unknown time-course of action, caffeine could potentially be transported directly from the nasal cavity to the CNS, specifically the cerebrospinal fluid and brain by intracellular axonal transport through two specific neural pathways, the olfactory and trigeminal [ , ].

No significant improvements were reported in either anaerobic and aerobic performance outcome measures despite the increased activity of cingulate, insular, and sensory-motor cortices [ 79 ].

Laizure et al. Both were found to have similar bioavailability and comparable plasma concentrations with no differences in heart rate or blood pressure Table 6.

While caffeinated gels are frequently consumed by runners, cyclists and triathletes, plasma caffeine concentration studies have yet to be conducted and only three experimental trials have been reported. Cooper et al. In the study by Cooper et al. In contrast, Scott et al.

utilized a shorter time period from consumption to the start of the exercise i. However, these ideas are based on results from independent studies and therefore, future studies may consider exploring the optimal timing of caffeine gel ingestion in the same group of participants.

More details on these studies may be found in Table 7. Similar to caffeinated gels, no studies measured plasma caffeine concentration following caffeinated bar consumption; however, absorption and delivery likely mimic that of coffee or caffeine anhydrous capsule consumption.

While caffeinated bars are commonly found in the market, research on caffeinated bars is scarce. To date, only one study [ 82 ] Table 7 has examined the effects of a caffeine bar on exercise performance.

Furthermore, cyclists significantly performed better on complex information processing tests following the time trial to exhaustion after caffeine bar consumption when compared to the carbohydrate only trial.

As there is not much data to draw from, future work on this source of caffeine is needed. A review by Trexler and Smith-Ryan comprehensively details research on caffeine and creatine co-ingestion [ 32 ].

With evidence to support the ergogenic benefits of both creatine and caffeine supplementation on human performance—via independent mechanisms—interest in concurrent ingestion is of great relevance for many athletes and exercising individuals [ 32 ].

While creatine and caffeine exist as independent supplements, a myriad of multi-ingredient supplements e. It has been reported that the often-positive ergogenic effect of acute caffeine ingestion prior to exercise is unaffected by creatine when a prior creatine loading protocol had been completed by participants [ , ].

However, there is some ambiguity with regard to the co-ingestion of caffeine during a creatine-loading phase e. While favorable data exist on muscular performance outcomes and adaptations in individuals utilizing multi-ingredient supplements e.

Until future investigations are available, it may be prudent to consume caffeine and creatine separately, or avoid high caffeine intakes when utilizing creatine for muscular benefits [ ].

This is likely due to the heterogeneity of experimental protocols that have been implemented and examined. Nonetheless, a systematic review and meta-analysis of 21 investigations [ ] concluded the co-ingestion of carbohydrate and caffeine significantly improved endurance performance when compared to carbohydrate alone.

However, it should be noted that the magnitude of the performance benefit that caffeine provides is less when added to carbohydrate i. carbohydrate than when isolated caffeine ingestion is compared to placebo [ ].

Since the publication [ ], results remain inconclusive, as investigations related to sport-type performance measures [ 83 , , , , , , ], as well as endurance performance [ 84 , , ] continue to be published.

Overall, to date it appears caffeine alone, or in conjunction with carbohydrate is a superior choice for improving performance, when compared to carbohydrate supplementation alone.

Few studies to date have investigated the effect of post-exercise caffeine consumption on glucose metabolism [ , ]. While the delivery of exogenous carbohydrate can increase muscle glycogen alone, Pedersen et al. In addition, it has been demonstrated that co-ingestion of caffeine with carbohydrate after exercise improved subsequent high-intensity interval-running capacity compared with ingestion of carbohydrate alone.

This effect may be due to a high rate of post-exercise muscle glycogen resynthesis [ ]. Practically, caffeine ingestion in close proximity to sleep, coupled with the necessity to speed glycogen resynthesis, should be taken into consideration, as caffeine before bed may cause sleep disturbances.

The genus of coffee is Coffea , with the two most common species Coffea arabica arabica coffee and Coffea canephora robusta coffee used for global coffee production.

While coffee is commonly ingested by exercising individuals as part of their habitual diet, coffee is also commonly consumed pre-exercise to improve energy levels, mood, and exercise performance [ 11 , 40 ].

Indeed, a recent review on coffee and endurance performance, reported that that coffee providing between 3 and 8. Specifically, Higgins et al.

Since the release of the Higgins et al. review, three additional studies have been published, examining the effects of coffee on exercise performance.

Specifically, Niemen et al. Fifty-km cycling time performance and power did not differ between trials. Regarding resistance exercise performance, only two studies [ 55 , 56 ] have been conducted to date.

One study [ 56 ] reported that coffee and caffeine anhydrous did not improve strength outcomes more than placebo supplementation. On the other hand, Richardson et al. The results between studies differ likely because it is challenging to standardize the dose of caffeine in coffee as differences in coffee type and brewing method may alter caffeine content [ ].

Even though coffee may enhance performance, due to the difficulty of standardizing caffeine content most sport dietitians and nutritionists use anhydrous caffeine with their athletes due to the difficulty of standardizing caffeine content.

Consumption of energy drinks has become more common in the last decade, and several studies have examined the effectiveness of energy drinks as ergogenic aids Table 8. Souza and colleagues [ ] completed a systematic review and meta-analysis of published studies that examined energy drink intake and physical performance.

Studies including endurance exercise, muscular strength and endurance, sprinting and jumping, as well as sport-type activities were reviewed. It has been suggested that the additional taurine to caffeine containing energy drinks or pre-workout supplements, as well as the addition of other ergogenic supplements such as beta-alanine, B-vitamins, and citrulline, may potentiate the effectiveness of caffeine containing beverages on athletic performance endeavors [ ].

However, other suggest that the ergogenic benefits of caffeine containing energy drinks is likely attributed to the caffeine content of the beverage [ ]. For a thorough review of energy drinks, consider Campbell et al.

Table 8 provides a review of research related to energy drinks and pre-workout supplements. Caffeine in its many forms is a ubiquitous substance frequently used in military, athletic and fitness populations which acutely enhance many aspects of exercise performance in most, but not all studies.

Supplementation with caffeine has been shown to acutely enhance many aspects of exercise, including prolonged aerobic-type activities and brief duration, high-intensity exercise. The optimal timing of caffeine ingestion likely depends on the source of caffeine.

Studies that present individual participant data commonly report substantial variation in caffeine ingestion responses. Inter-individual differences may be associated with habitual caffeine intake, genetic variations, and supplementation protocols in a given study.

Caffeine may be ergogenic for cognitive function, including attention and vigilance. Caffeine at the recommended doses does not appear significantly influence hydration, and the use of caffeine in conjunction with exercise in the heat and at altitude is also well supported.

Alternative sources of caffeine, such as caffeinated chewing gum, mouth rinses, and energy gels, have also been shown to improve performance. Energy drinks and pre-workouts containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance. Individuals should also be aware of the side-effects associated with caffeine ingestion, such as sleep disturbance and anxiety, which are often linearly dose-dependent.

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