It’s All About Speed!

Michael Sowers - Princeton Photo by Tommy Gilligan

How To Train For Speed In The Gym

Can you train to play like Michael Sowers?

No.

Can you focus on a few qualities that Michael exhibits and potentially get a little quicker to help develop your game more?

Yes, you absolutely can.

First, lets breakdown Michael’s game to assess which of his attributes we can and cannot train for.

A very brief scouting report on Michael Sowers:

-Insane stop/start capabilities (Acceleration/Deceleration)

-Times his rolls/splits very well, can accelerate quickly out of them to beat you topside or back underneath

-Tremendous vision and lacrosse IQ

-Righty/Lefty, excellent and dangerous with both hands

In the gym, we can work on the first two bullet points. The vision, Lax IQ, and the stick skills/capabilities are all areas of your game that you will have to work on outside of the gym. However, the ability to stop & start on a dime, explode and accelerate out of your dodges? We can pick and choose different exercises and training methods to elicit adaptations to make you faster, stronger, and more powerful.

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The Principle of Myoplasticity:

The principle that our muscle(s) will and can change and adapt to our lifestyle and how we use them. Your body will create changes at the cellular level deep in your muscles in response to whatever you do with it, and if you repeat those same movements your body will begin to change and adapt in order to become more efficient at performing them the next time around. So if you want to move fast out on the field, why aren’t you doing every rep in the gym or every run on the field fast? It translates.

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Let’s analyze this still frame. Notice how low Michael’s body is to the ground as he’s changing direction. We call this lowering your center of mass and it allows you to stay balanced while you decelerate, re-position yourself quickly and efficiently, and then accelerate in a new direction. How quickly you transition between that deceleration and acceleration phase determines how quick and shifty you are as a player.

So how can we improve this in the gym?

Improve mobility: Work on hip and ankle mobility so that you are able to get low enough to the ground to change direction quickly. Before jumping into a strength and conditioning program focused on speed and power, make sure you have prepared your body to handle that amount of stress and training first. Make sure you have mastered the basics first. You should be able to do all basic bodyweight movement patterns (lunges in any direction, squats, crawls, etc.) first without any issues or major compensations. The first several training blocks for most beginners will be focused on mastering basic movement patterns and creating neural adaptations to better and more efficiently contract and utilize your muscles. If you are already an experienced lifter and are entering your first phase of off-season training, a similar block will be used for the first 3-4 weeks in order to rehab the body from a rough season and focus on strengthening your tendons and connective-tissues. This phase for experienced lifters would only last 1-2 blocks (3-4 weeks in each block) depending on their needs. These blocks will include exercises that are multi-joint and put the muscle through its full range of motion.

Training Tip: Tempos can be added to rep schemes to work on mastering movement patterns and add mobility. I like slow lowers (eccentrics) and slow raises (concentrics) for grooving movement patterns and isometric holds at the bottom of exercises to enhance mobility.

Improve deceleration by being stronger unilaterally and eccentrically. Simply put, the stronger you are on 1 leg, especially during the lowering phase of movement, the better you will be at decelerating your bodyweight while you change direction. In order to master deceleration, you need to have built up a significant amount of strength in your legs to handle that load. There’s a reason Jordan Wolf was squatting over 500 pounds and absolutely dusting kids on the field,

Training Tip: Add 4-5 second eccentrics in your 1-leg exercises to train deceleration and pack on lean muscle. Loading eccentrics is more metabolically efficient (not chewing up as much ATP) and stimulates hypertrophy (creates more micro-tears) than focusing on the concentric portion of the rep. You’re also much stronger eccentrically than you are concentrically, but before you begin to load these exercises up make sure you have created a proper base of strength and mobility.

Improve acceleration! A lot of talk is spent on improving speed, but how often are we able to run a clean 50-60yd sprint in a lacrosse game without having to dodge or avoid opponents? The emphasis should be put on acceleration, and really how quickly we can cover those first 10-30 yards. Analysis of team sport athletes by Struzik and colleagues showed that in competition scenarios, 49% of all sprints were shorter than 10 yards, and 96% were under 30 yards. Be fast and powerful on those first few steps, and you’ll start looking more and more like Mike.

Citation: Struzik A, Konieczny G, Stawarz M, Grzesik K, Winiarski S, Rokita A. Relationship between Lower Limb Angular Kinematic Variables and the Effectiveness of Sprinting during the Acceleration Phase. Applied Bionics and Biomechanics. 2016;2016:1-9

Acceleration can be improved by working on 3 things:

1) Acceleration and sprint technique (45 degree body & shin angle, triple extension & flexion of ankle/hip/knee,)

2) The amount of force we’re putting into the ground (ie single leg strength/power)

3) How quickly we are producing that force into the ground (rate of force production).

Training Tip: Acceleration & Sprint Technique: Incorporate these pre and post-training. Any variation of wall strikes, skips, and bounds can be used right after warming up to groove good movement patterns prior to practice, lifting, or doing sprints. Incorporate them post-practice/training for 2 reasons:

• i. Acts as a low-intensity cool-down. Cool-downs can accelerate lactate removal from the blood, control the decline in body temperature and blood flow post-exercise, and may also benefit the immune system as abrupt changes in body temperature from exercise can leave an athlete vulnerable to illness or minor infections for up to several hours post-exercise.

• ii. Helps you work on proper sprint technique when you’re fatigued. When you’re tired, one of the first things you lose is technique; whether thats in your stick positioning, posture, or movement patterns. Doing these after practices or training sessions will help reinforce these techniques so you don’t lose them in the 2nd half come game time.

Free Sample Speed Program

Day 1 is built for improving acceleration and power. This is a high-intensity lift, every rep needs to be deliberate and explosive!

Day 2 is focused more on mobility and deceleration. Tempos are added to exercises to stress either the eccentric or isometric portions of the movement to stimulate strength and growth.

Lit Review: Resistance Training For Children & Youth

Many preconceptions exist about the efficacy and safety of resistance training in preadolescent children. Exercise has been shown to benefit the human body, especially in adolescents and adults, and research in the field of resistance training has indicated a positive correlation with training and increases in muscular strength, bone mineral density, motor coordination, and body composition (3-10,13,15). Preadolescence is a crucial time for the growth and development of the skeleton as well as the muscles and connective tissues that surround it (8). The arguments against resistance training are primarily concerned with the impact that these weight bearing loads have on the growing bones and the safety issues that surround children performing complicated weight lifting techniques (7-9). Stunted growth, decreased strength levels, and epiphyseal plate damage are all concerns that are associated with resistance training in this population (7,8). However, much of the literature that has studied the effect of resistance training in children show a positive impact on bone health and strength development when properly prescribed and supervised (1-10,12-15).

Impact on Bone Mineral Density

Numerous studies have shown a positive correlation between resistance training and increases in areal bone mineral density in children (3,4,7-9). This acquisition of greater bone density early in life appears to carry over into adolescence, suggesting moderate resistance training before puberty may be effective in reducing age-related bone loss and damage (3,4, 7-9). Faigenbaum et al. suggest that participation in sports and resistance training at this age is critical to the remodeling and strengthening of bones that may lead to performance and health benefits in the future (8). Much of the literature concerning the possible negative impact of strength training on growth and development references the reduction in height of young gymnasts; whether or not this is primarily due to the vigorous intensity of gymnastics or selection for specific body types for this sport has not been fully determined, but it’s also hypothesized that this reduction in growth could be due to insufficient nutritional intake that does not match the high energy expenditure experienced in this sport (3).

To study the effects of exercise on bone mineral density, Bass et al. compared prepubertal and retired female gymnasts to control groups matched for skeletal age in the prepubertal group, and age, height, and weight for the retired gymnast group. Areal bone mineral density was found to be 30-85% greater in the prepubertal gymnastics group compared to the control (3). The retired gymnasts also exhibited a higher areal bone mineral density than their matched control group even after 20 years of being removed from the sport (3). Bass et al. findings suggest that this increase in bone mass during there prepubertal years was retained by the gymnasts into adulthood (3). These findings are consistent with previous literature that have noticed a retention of high bone mineral density in retired athletes and weight lifters (3,4,8,9). Bradney et al. found similar results in pre-pubertal boys that had participated in an 8-week, 30 minute, moderately intense weight bearing training session performed 3 days a week. At the conclusion of this study the exercised group exhibited an increase in areal bone mineral density that was double the amount found increased in the control group (4). These increases in bone mineral density appear to be specific to the bones that are involved in the weight bearing aspect of the exercise (3,4). Exercise seems to increase periosteal and endocortical apposition of bone at the weight-bearing site, however what is not yet known is the impact that various exercise intensities and durations have on bone acquisition and growth during the different stages of puberty (3,11).

Impact on Strength & Power

Resistance training in children do result in increases in muscular strength (5-10). Similar to adolescents, much of the gain in muscular strength is due to neurological adaptations to resistance training (3,7-9,13). Increases in muscle size also aid in the development of muscular strength, but to a much lesser degree (7-9). Following a 12-week strength training program prepubescent and postpubescent children were able to improve there 10 rep max strength, motor capabilities, and flexibility compared to a non-exercised control group (13). Different kinds of training have been studied in children in order to determine which strength gains would carry over most into athletic performance. A power training regimen would consist of high velocity, explosive movements such as plyometrics, box jumps, and hurdle hops (6,8,9). Strength training focuses on slower velocity repetitions and greater external loading than power training (6,8,9). Behm et al. reviewed 107 studies to compare the effectiveness of both training modalities on sprint, strength, and jumping measures. Power training was found to impact measures of power, broad and vertical jump, better than strength training (6).  However, in trained youth, Behm et al. found that strength training improved sprint measures more than power training and also generated greater lower limb strength (6). The previously untrained individuals differed from their trained counterparts in these findings, as power training impacted sprint measures more than strength training (6). The general consensus in this fields of research is not to choose between the two training modalities, but to instead incorporate both techniques to create a balanced training regimen (8,9). Overall, the literature regarding resistance training in children has been immensely positive (1-10,12-16). The potential benefits of resistance training closely coincide with the benefits exhibited in the adult population. Increases in muscular strength, power, endurance, and bone mineral density have all been noted (3-10,13,15).

 What The Researchers Suggest

Guidelines for children engaging in resistance training should begin with proper supervision and need to be introduced to basic movement patterns (Push, Pull, Squat, Hinge, Jump, Sprint, Crawl). When developing a training program for a youth athlete it is important to focus on the training frequency, intensity, and volume of the workout as well as the order and selection of exercises. Faigenbaulm et al. suggest resistance training 2-3 days per week on non-consecutive days. These workouts should be performed at a low-moderate intensity (7,8). Prior to the strength training session, it is suggested that a 5-10 minute dynamic warm-up be performed at a moderate-high intensity(7,8). This will begin to excite the motor units of the muscles, increase core body temperature, and improve flexibility and range of motion (7,8). Training sessions should focus on balancing both upper and lower limb extremity exercises as well as incorporate movements that challenge the child’s core, balance, and proprioceptive skills (7,8). Whether the specific exercise is focused more on power or strength, 1-3 sets are recommended for both types (7,8). Repetition ranges for strength training should ideally be between 6-16, whereas power exercises are generally performed for no more than 6 repetitions in one set (7,8). Research suggests children are able to recover from exercise more quickly than adults are, therefore 1-2 minutes rest will most likely be sufficient for the child to adequately recover in between sets (7,8). At the end of the workout, a cool-down consisting of light calisthenics work as well as static stretching is recommended (8).

References:

1.    Alves, AR. Concurrent training in prepubescent children: the effects of 8 weeks of strength and aerobic training on explosive strength and VO2MAX. Journal of Strength and Conditioning Research, vol. 30, no. 7, pp. 2019–2032, 2016

2.    Alves, AR. Effects of order and sequence of resistance and endurance training on body fat in elementary school-aged girls. Biology of Sport, vol. 34, no. 4, pp. 379–384, 2017 

3.    Bass, S. Exercise before puberty may confer residual benefits in bone density in adulthood: studies in active prepubertal and retired female gymnasts. Journal of Bone and Mineral Research. Vol. 13, no. 3, 1998

4.    Bradney, M. Moderate exercise during growth in prepubertal boys: changes in bone mass, size, volumetric density, and bone strength a controlled prospective study. Journal of Bone and Mineral Research. Vol. 13, no. 12, 1998 

5.    Behm, DG. Canadian society for exercise physiology position paper: resistance training in children and adolescents. Applied Physiology, Nutrition, and Metabolism, vol. 33, no. 3, 2008 

6.    Behm, DG. Effectiveness of traditional strength vs. power training on muscle strength, power and speed with youth: a systematic review and meta-analysis. Frontiers in Physiology 2017

7.    Faigenbaum, AD. Youth resistance training: updated position statement paper from the national strength and conditioning association. The Journal of strength and conditioning research, vol. 23, 2009

8.    Faigenbaum, AD. Pediatric resistance training: benefits, concerns, and program design considerations Current Sports Medicine Reports, vol. 9, no. 3, pp. 161–168, 2010 

9.    Faigenbaum, AD. Youth resistance training: the good, the bad, and the ugly-the year that was 2017. Pediatric Exercise Science, vol. 30, no. 1, pp. 19–24, 2018

10. Ferrete, C. Effect of strength and high-intensity training on jumping sprinting, and intermittent endurance performance in prepubertal soccer players. Journal of Strength and Conditioning Research, vol. 28, no. 2, pp. 413–422, 2014 

11.  Frisch, RE. Delayed menarche and amenorrhea of college athletes I relation to age of onset of training. Journal of American Medical Association 246;1559-1563. 1982

12. Gabler, M. The effects of concurrent strength and endurance training on physical fitness and athletic performance in youth: a systematic review and meta-analysis. Frontiers in Physiology, vol. 9, 2018

13. Lillegard, WA. Efficacy of strength training in prepubescent to early postpubescent males and females: Effects of gender and maturity. Pediatric Rehabilitation, 1:3, 147-157, 1997

14. Marta, CC. Differentiating maturational influence on training-induced strength and endurance adaptions in prepubescent children. American Journal of Human Biology, vol. 26, no. 4, pp. 469–475, 2014 

15. Myers, AM. Resistance training for children and adolescents. Translational Pediatrics, vol. 6, no. 3, pp. 137–143, 2017

16. Tsolakis, CK. Strength adaptations and hormonal responses to resistance training and detraining in preadolescent males. Journal of strength and conditioning research, 18(3), 625-629, 2004

Supplement Review: Caffeine

Caffeine has been studied as far back as 1907 as an ergogenic aid for sports performance. The ergogenic effects on sports performance have been thoroughly observed in endurance athletes (2,5,6,8-10,12,14) and more recent studies have shown improvements on several anaerobic performance measures as well (1,3,4,7,9,13,16). There are several plausible mechanisms that attempt to identify caffeine’s impact on improved endurance, strength, and power through increases in lipolysis, excitatory neurotransmitter release, and/or the maintenance of the motor neurons resting membrane potential. Certain genetic variants may also impact the ergogenic effects and side-effects elicited from caffeine supplementation. In order to make practical recommendations on caffeine supplementation for athletes, many variables need to be taken into account. A better understanding of caffeine’s mechanisms of action as well as several potential genetic predispositions and their corresponding phenotypes will allow for more precise caffeine recommendations to be made

The use of caffeine on aerobic performance and muscular endurance is well documented (2,5,6,8-10,12,14). Endurance performance has been evaluated in several ways, either through time-to-exhaustion (2) or time-trial protocols (6). Time-to-exhaustion studies have participants exercising at a set submaximal intensity until voluntary fatigue occurs. Bell and Mclellan observed the effects of caffeine ingestion on repeated exhaustive performance in nine male athletes and found that 5mg/kg of caffeine was able to increase time-to-exhaustion by 24.9 +/- 10.2 minutes in the morning session and 21.5 +/- minutes in the evening session. Bell and Mclellan’s results are consistent with similar studies showing caffeine ingestion is able to improve endurance performance through anti-fatigue mechanisms (5,8,10). However, time-to-exhaustion protocols do not accurately simulate athletic competition, as Ganio et al states in their systematic review; most sporting events are focused on performance in a set amount of time or are more time trial based (6). Time-to-exhaustion protocols are also highly susceptible to type I errors as minute changes in overall power output, which may not be significant in a time trial protocol, can elicit very large changes in time-to-exhaustion performance, rendering false positives (6). Ganio et al focused their systematic review on caffeine’s effect on studies using time trial protocols. Regardless of when caffeine was ingested, on average, caffeine improved performance by 3.2 +/- 4.3% over the placebo (6). Caffeine ingested before time-trial protocols elicited an improvement of 2.3 +/- 3.2%  compared to 4.3 +/- 5.3% when caffeine was ingested prior and during testing (6). Out of the 33 studies that were included in the time-trial systematic review, 30 observed enhanced performance with caffeine ingestion and 15 of those were noted as being statistically significant (6). Endurance improvements were observed with caffeine dosages of greater than 3mg/kg and no changes in improvement were observed with increasing dosages up to 9mg/kg (6).

Studies involving high-intensity exercise also show improvements on several anaerobic measures after caffeine ingestion (7,9,13,16). In a recent systematic review and meta-analysis by Grgic et al, caffeine ingestion was shown to improve anaerobic measures of strength and power. 10 studies were reviewed for their anaerobic strength measures via 1RM testing. Upper body strength was found to be significantly improved following caffeine ingestion, while there was little to no effect on lower body strength (9). Grgic et al’s review of caffeine’s impact on anaerobic strength conflicts with previous theories that suggested caffeine would have a greater effect on larger muscles, which are mainly located in the lower body (9). An additional 10 studies were reviewed for anaerobic power, measured mainly via vertical jump and one using a Wingate test. Similar to strength, anaerobic power measures were improved after the ingestion of caffeine. Acute caffeine suggestion prior to vertical jump tests was reported to having as significant an impact on performance as 4 weeks of plyometric training (9).  Increases in strength and power translate to increased performance in competition in many sporting events, and caffeine ingestion prior will most likely enhance performance.

While previous systematic reviews state that caffeine’s ergogenic effects on endurance did not vary between modes of delivery (6), Grgic’s review found significant increases in strength and power when caffeine was ingested via capsules (9).  Habitual caffeine use may also impact the degree to which caffeine acts as an ergogenic aid. Bell and Mclellan observed greater improvements in performance for non-users versus habitual users (2). Further studies have reported enhanced performance in subjects that abstained from caffeine use 2-4 days prior to testing (6).

Caffeine, 1,3,7-trimethylxanthine, is a member of the methylxanthine family and is metabolized in the liver by cytochrome P-450 (8,14,18). Theobromine, paraxanthine, and theophylline are metabolites of coffee and are responsible for its downstream ergogenic effects (8,14). Theobromine induces vasodilation, Theophylline stimulates the adrenal medulla to release the excitatory neurotransmitter epinephrine, and paraxanthine has been associated with increases in the mobilization of free fatty acids (1,8).

Adenosine acts as a key regulator for a number of processes and has inhibitory effects on the central nervous system making it harder for the body to recruit muscle (3). However, this inhibitory effect of adenosine may be alleviated through caffeine ingestion. Caffeine and its metabolite theophylline can antagonistically bind to adenosine receptors, preventing an influx of inhibitory signals sent via adenosine binding (8). Increases in excitatory neurotransmitters from caffeine ingestion will allow for more ligand gated ion channels on the synapse of motor neurons to be activated, reducing the time it takes for an action potential to be generated as more calcium and sodium will enter the soma to depolarize the membrane. Within one hour of caffeine ingestion elevated plasma epinephrine concentrations are observed both at rest and during exercise (8). Caffeine could also impact the threshold potential for muscle contraction via translocation of calcium ions between plasma and the sarcoplasmic reticulum, allowing for greater stimulus of ryanodine receptors on the sarcoplasmic reticulum (8).

Caffeine may improve aerobic performance via increased calcium build-up in the cisternae of sarcoplasmic reticulum and increase plasma epinephrine, both of which increase the activity of phosphorylase a, an enzyme that breaks down glycogen into glucose to be used as fuel for glycolysis. Other plausible mechanisms that may account for the anti-fatigue properties of caffeine focus on the attenuation of high extracellular potassium concentrations and also increasing intracellular calcium concentrations. High extracellular potassium concentrations are often observed after high-intensity exercise and correspond with reduced excitability of neurons, lower conduction velocities, and increased fatigue (3). Caffeine may positively impact resting membrane potentials by increasing circulating catecholamine concentrations that increase the activity of sodium-potassium pumps (3). Maintaining resting membrane potentials allow for excitatory neurotransmitters to be more effective at generating action potentials that result in more efficient muscle contractions, thus increasing endurance. Through these mechanisms, caffeine and its metabolites can enhance sports performance by increasing power output, decreasing the rate of perceived exhaustion, and delaying fatigue.

From Skinner, J. and D. Morgan.  Aspects of anaerobic performance.  In Limits of Human Performance.  Champaign:  Human Kinetics Publishers, 1984, pp. 31-44

As the intensity of exercise approaches an individuals vo2max and the duration decreases our body begins to progressively use more of our anaerobic system to fuel performance. Our anaerobic system runs on ATP provided from high energy phosphates and from the breakdown of glucose and glycogen that our body has stored from ingested foods. High-intensity exercise demands our muscles to produce high power outputs. The principle of orderly recruitment staes that our body will recruit just enough muscle to satisfy the demand in external force. For maximum intensity exercises like 1RM’s, your body will recruit all of your fast-twitch muscle fibers in order to produce the most amount of power and strength, while only lifting 50% of your 1RM will recruit just enough muscle to lift that load. These fast twitch fibers are very glycolytic and run on ATP supplied mainly from anaerobic glycolysis during high intensity exercise. The recruitment of muscle fibers begins with the generation of action potentials at the axon hillock of motor neurons. Action potentials will only be sent if the resting membrane potential along the axon hillock is depolarized by 15-20 millivolts in which a threshold is surpassed allowing for a rapid influx of sodium into the membrane. Excitatory neurotransmitters like epinephrine or glutamate will bind to receptors on the membrane of the motor neuron, activating ion channels that permit an influx of calcium and sodium into the soma. This influx of cations elicits small depolarizations along the membrane that can build up to meet the threshold potential needed to send an action potential. The smaller the cell body of the motor neuron the quicker this threshold will be met to activate its muscle fibers. Your body will progressively excite more motor neurons until enough muscle fibers are recruited to match the demand in force. Increases in plasma excitatory neurotransmitters from caffeine ingestion may help initiate more action potentials and recruit and contract more muscle fibers faster and with greater force, as research has shown (1,8,9). Caffeine and its metabolites may also help maintain resting membrane potentials by increasing the activity of ATPase sodium-potassium pumps (1,8,9).  

Powers et al Exercise Physiology: Theory and application to fitness and performance, Chapter 5: Cell Signaling and the Hormonal Responses to Exercise

            Intense bouts of exercise that last less than a minute will require much more of the anaerobic system, while exercise that persists longer than 10 minutes almost entirely relies on the aerobic system to supply ATP to the working muscle. Increasing the duration of exercise is associated with rises in epinephrine, glucagon, cortisol, and growth hormone concentrations, all of which signal the body for glycogen and fat breakdown in order to generate ATP. Fat is a much more abundant fuel source and produces more ATP than any other macronutrient. However, fat takes a longer time to be metabolized and fed into the Krebs cycle as Acetyl CoA. Caffeine ingestion has been proposed to enhance endurance performance by increasing fat breakdown and sparing muscle glycogen, however recent systematic reviews did not report any significant changes on muscle glycogen levels (1). Caffeine may enhance fat breakdown via elevated plasma epinephrine levels. Epinephrine can bind to G-protein coupled receptors on the membrane of adipose tissue and increase the activity of hormone sensitive lipase, the enzyme primarily responsible for the breakdown of triglycerides into free fatty acids to be used by our aerobic system. Caffeine ingestion prior to exercise may increase lipolysis by elevating plasma epinephrine levels to a higher degree. This may be a mechanism by which caffeine improves time-to-exhaustion performance.

Although the literature shows that caffeine ingestion can improve exercise performance, and on average does, numerous studies also show that some subjects do not receive any performance enhancing effects with caffeine. Womack et al were the first to test whether genetics may explain the differences observed on the ergogenic effects of caffeine between subjects. They identified a single nucleotide polymorphism, rs762551, on the CYP1A2 gene that codes for cytochrome P450. As mentioned previously, cytochrome P450 is located in the liver and is responsible for the metabolism of caffeine. Caffeine ingestion of 6mg/kg prior to a 40-kilometer time trial cycle race revealed that subjects expressing the homozygous A allele for this single nucleotide polymorphism responded more favorably to the caffeine treatment than subjects expressing the C allele (18). These findings suggest that individuals with homozygous A alleles can metabolize caffeine much quicker and will elicit greater ergogenic benefits from caffeine (18). Another single nucleotide polymorphism has been identified that may possibly impact a subject’s acute response to caffeine. Located on ADORA2A, a gene coding for adenosine receptors, the snp rs5751876 may determine if an individual will elicit any beneficial or detrimental effects from caffeine. TT homozygotes for this gene were able to utilize caffeine to enhance performance, while those expressing the C allele did not benefit as much (14).  This snp was also associated with increased anxiety following caffeine ingestion for TT carriers and reduction in sleep quality for C allele carriers (14).

Genetic and non-genetic factors influencing caffeine ingestion decisions (14)

Practical guidelines for caffeine supplementation in order to enhance athletic performance should take these possible genetic factors into account. Since most athletes will not be able to be genotyped in order to identify which allele configuration they express, each individual should use trial and error to determine what the best dosage of caffeine is for them personally. Even for habitual users, abstaining from caffeine for 7 days is recommended in order to return caffeine sensitivity back to baseline levels (6). Once the athlete has returned to baseline sensitivity, 3-6 mg/kg of should be ingested one hour prior to exercise. If the athlete feels increasingly anxious with increasing amount of caffeine, they may express the homozygous TT genotype for adenosine receptors, this suggests they are more sensitive to the ergogenic effects of caffeine and could possibly benefit from lower doses (14). If the subject finds sleep is easily disrupted with even minimal ingested amounts of caffeine, the C allele for ADORA2A may be present, and caffeine use is recommended only when the need for performance enhancement outweighs the need for quality sleep that night (14). If the athlete feels that caffeine ingestion significantly improves their performance, they may be fast metabolizers of caffeine, likely containing the homozygous A alleles for cytochrome P450 (14,18). These individuals may benefit from following general guidelines for caffeine supplementation recommending 3-6mg/kg be ingested 30-60 minutes prior to exercise. If little to no effect on exercise performance is experienced following these general guidelines, they may contain the C allele and will metabolize caffeine much slower (14,18). These individuals may still benefit from caffeine’s ergogenic effects if ingested more than an hour before the start of exercise and/or at higher dosages (14). Performance enhancement may also be modulated by its mode of delivery. Caffeine administered via capsule form was shown to elicit greater improvements on strength and power (9). Therefore it may be beneficial to use caffeine capsules prior to exercise like weight lifting or high intensity sports that are enhanced by increased force production.

Studies have consistently shown that caffeine ingestion is able to improve exercise performance in a majority of subjects. These improvements in performance have been observed for both aerobic and anaerobic measures (1-13,16). However, some individuals may contain specific genetic variants that could require differences in dosing or time ingested prior to exercise in order to elicit similar performance enhancing effects (14, 18). All in all, the literature on the ergogenic effects of caffeine show that caffeine ingestion in the right amount and at the right time may enhance performance in nearly all subjects, no matter the duration and intensity of exercise.

References:

1.     Astorino, TA and Roberson, DW. Efficacy of acute caffeine ingestion for short-term high-intensity exercise performance: A systematic review. J Strength Cond Res 24(1): 257-265, 2010.

2.     Bell DG, Mclellan TM. Effect of Repeated Caffeine Ingestion on Repeated Exhaustive Exercise Endurance. Medicine & Science in Sports & Exercise. 2003;35(8):1348-1354.

3.     Bowtell JL, Mohr M, Fulford J, et al. Improved Exercise Tolerance with Caffeine Is Associated with Modulation of both Peripheral and Central Neural Processes in Human Participants. Front Nutr. 2018;5:6. Published 2018 Feb 12.

4.     Boyett JC, Giersch GE, Womack CJ, et al. Time of Day and Training Status Both Impact the Efficacy of Caffeine for Short Duration Cycling Performance. Nutrients. 2016;8(10):639. Published 2016 Oct 14. doi:10.3390/nu8100639

5.     Burke, L.M. Caffeine and Sports Performance.  Applied Physiology, Nutrition, and Metabolism, 2008, 33(6): 1319-1334.

6.     Ganio, M. et al. Effect of caffeine on sport-specific endurance performance: a systematic review. J Strength Cond Res 23(1): 315-324, 2009.

7.     Goods PS, Landers G, Fulton S. Caffeine Ingestion Improves Repeated Freestyle Sprints in Elite Male Swimmers. J Sports Sci Med. 16(1):93-98, 2017

8.     Graham T, Soeren MV. Caffeine and Exercise: Metabolism and Performance. Canadian Journal of Applied Physiology, p111-138, 1994

9.     Grgic J, Trexler ET, Lazinica B, Pedisic Z. Effects of caffeine intake on muscle strength and power: a systematic review and meta-analysis. J Int Soc Sports Nutr. 2018;15:11. Published 2018 Mar 5

10.  Hodgson AB, Randell RK, Jeukendrup AE. The Metabolic and Performance Effects of Caffeine Compared to Coffee during Endurance Exercise. PLoS ONE 8(4): e59561, 2013

 11.  Ivy JL, Costil DL, Fink WJ, Lower RW. Influence of caffeine and carbohydrate feedings on endurance performance. Med Sci Sports 11: 6-11, 1979

12.  Loureiro LM, Reis CE, Costa TH. Effects of Coffee Components on Muscle Glycogen Recovery: A Systematic Review. International Journal of Sports Nutrition and Exercise 28(3): p284-293, 2018

13.  Moore J, McDonald C, McIntyre A, Carmody K, Donne B. Effects of acute sleep deprivation and caffeine supplementation on anaerobic performance. Sleep Sci; 11(1):2-7, 2018

14.  Pickering, C., & Kiely, J. Are the Current Guidelines on Caffeine Use in Sport Optimal for Everyone? Inter-individual Variation in Caffeine Erogenicity, and a Move Towards Personalized Sports Nutrition. Sports medicine (Auckland, N.Z.), 48(1), 7-16. 2017.

15.  Saville, Christopher W. N., et al. “Effects of Caffeine on Reaction Time Are Mediated by Attentional Rather than Motor Processes.” Psychopharmacology, vol. 235, no. 3, pp. 749–759, 2017.

16.  Souissi, Makram, et al. “The Effects of Caffeine Ingestion on the Reaction Time and Short-Term Maximal Performance after 36h of Sleep Deprivation.” Physiology & Behavior, vol. 131, pp. 1–6, 2014.

17.  Stephenson D. G. Caffeine - a valuable tool in excitation-contraction coupling research. The Journal of physiology, 586(3), 695-6, 2008.

18.  Womack, C.J. et al.  The influence of a CYP1A2 polymorphism on the ergogenic effects of caffeine.  Journal of the International Society of Sports Nutrition, 9:7, 2012.