Recovery and athletic performance is an important topic, and one that gets a fair bit of attention. However, information disseminated about recovery modalities often prioritize cumbersome methods with a poor return on investment. As is often the case the fundamentals take a back seat to elaborate strategies to improve athletic performance. When in reality optimization must start with and always prioritize the fundamentals. The objective of this article is to compile all relevant information on recovery and present a comprehensive analysis on the various strategies. From there we can develop a hierarchical structure to offer pragmatic recommendations for athletes to get the most out of their training and recovery and avoid prioritizing variables that generate a small magnitude of effect.
Recovery and athletic performance is an important topic, and one that gets a fair bit of attention. However, information disseminated about recovery modalities often prioritize cumbersome methods with a poor return on investment. As is often the case the fundamentals take a back seat to elaborate strategies to improve athletic performance. When in reality optimization must start with and always prioritize the fundamentals. The objective of this article is to compile all relevant information on recovery and present a comprehensive analysis on the various strategies. From there we can develop a hierarchical structure to offer pragmatic recommendations for athletes to get the most out of their training and recovery and avoid prioritizing variables that generate a small magnitude of effect.
The Role Of Sleep In Athletic Performance:
A 2007 crossover study by Reilly et al. found that sleep restriction had a significant impact on performance. Subjects were restricted to three hours of sleep per night and were not permitted to ingest caffeine or any other substance that may interfere with physiological or cognitive performance. The trial lasted four days and the subjects were involved in a sub-maximal and maximal strength program.
Although subjective assessments of exertion increased after the fist night of sleep restriction, a uniform reduction in performance across all exercises was not observed until the fourth day (1). Mood however was negatively impacted after just one night of sleep restriction with subjects reporting increased confusion, fatigue, sleepiness, and decreased vigour (1).
A 2019 study found dynamic instability along with reduced joint coordination and reaction time in elite cyclists when sleep was restricted (2). Blunted coordination of multijoint tasks is likely impacted by impaired cognitive responses resulting from perceived fatigue. This is in line with other research findings suggesting reaction time, coordination, speed and motor performance degrade at a faster rate than maximal strength (3)(4)(5). However, one study found a more pronounced decrease in performance at sub maximal loads (5). This is at least partly influenced by the negative impact sleep deprivation has on mood and thus motivation to sustain strenuous training.
A 2003 paper by Belenky et al. found “Seven days of sleep restriction degraded psychomotor vigilance performance in a sleep-dose-dependent manner. With mild to moderate sleep restriction (7- and 5-h Tine In Bed), performance initially declined and, after a few days, appeared to stabilize at a lower-than-baseline level for the remainder of the sleep restriction period. In contrast, with severe sleep restriction (3-h Time In Bed) performance declined continuously across the sleep restriction period, with no apparent stabilization of performance” (6).
There was also an observed difference between acute and chronic sleep restriction. While acute restriction permitted a more rapid return to baseline performance and cognitive function, chronic restriction lead to adaptive changes that blunted return to baseline and extended the timeline of impaired performance (6). Although strength characteristics seems to be more resilient to sleep restriction, several studies have reported slower sprint times, reduced glycogen concentration and decreased force output and muscular strength (7)(8)(9)(10).
Additionally there seems to be a significant genetic component to chronobiology with one paper finding roughly 45% of the variance between morning and evening chronotypes were explained by heritability (11). Researchers have found the preponderance of males had a bias toward evening chronotypes where females had a bias toward morning chronotypes (11)(12). Advanced age is also associated with morning chronotypes (13). The findings also suggest that morning vs evening chronotypes have a strong genetic influence that take root early in adolescence.
There are three categories of chronotypes, morning, evening and no-type. Each chronotype shows peaks of several psychophysiological variables at their corresponding times (14). Thus morning chronotypes experience this peak earlier in the day than evening types. A 2017 systematic review found “Chronotype influences ratings of perceived exertion and fatigue scores in relation to submaximal and self-paced physical tasks performed in the morning: morning types (M-types) seem to have more of an advantage because they are less fatigued in the first part of the day than neither types (N-types) and evening types (E-types)” (14).
Thus there appears to be grounds for adjusting training time based on an athletes chronotype. However, I feel the need to highlight the opportunity cost associated with such an adjustment. If lifestyle factors interfere with alterations in training time the additional burden may outweigh any potential benefits of training adjusted to align with psychophysiological peaks. Therefore such decisions should be considered carefully.
A paper titled “Insufficient sleep undermines dietary efforts to reduce adiposity” found that sleep restriction had a significant impact on body composition. The randomized two-period two-condition crossover study spanned 14 days and restricted sleep as well as caloric intake. The researchers found total weight lost was identical between groups but the sleep restricted group lost 60% more lean mass and 55% less fat mass (15). This is especially relevant for individuals who are dieting to compete within a given weight class.
Sleep restriction also impacts your neuroendocrine system. A 2004 paper found “Sleep restriction was associated with average reductions in the anorexigenic hormone leptin (decrease, 18%; P 0.04), elevations in the orexigenic factor ghrelin (increase, 28%; P < 0.04), and increased hunger (increase, 24%; P < 0.01) and appetite (increase, 23%; P 0.01), especially for calorie-dense foods with high carbohydrate content (increase, 33% to 45%; P 0.02)” (16). The increased hedonic drive for energy dense and highly palatable foods can be a significant barrier to either maintaining or improving body composition for athletic performance. Since lower body fat percentages in strength athletes allows for increasing contractile tissue, sleep restriction creates an unnecessary obstacle to performance optimization.
Although sleep restriction research is abundant, studies exploring sleep extension are less common. However, the current evidence in support of sleep extension for improved athletic performance is quite promising. A 2011 paper by Mah et al. looked at athletic performance of college basketball players in response to sleep extension. The researchers found “Shooting accuracy improved, with free throw percentage increasing by 9% and 3-point field goal percentage increasing by 9.2% (P < 0.001). Mean PVT reaction time and Epworth Sleepiness Scale scores decreased following sleep extension (P < 0.01). POMS scores improved with increased vigour and decreased fatigue subscales (P < 0.001). Subjects also reported improved overall ratings of physical and mental well-being during practices and games” (17). This improvement in performance demonstrates the positive impact on psychomotor skills which admittedly are less important in strength sports, but still play an important role in the execution of competitive lifts.
Researchers have also observed athletes in general demonstrate suboptimal sleep behaviour (18)(19)(20). There also seems to be inter-individual differences in sleep patterns that impact the outcomes of sleep extension, some of which are likely based on the athletes normative sleep habits. However the benefits of reducing the sleep debt of an athlete appear to be significant. Some of them being improved immune function, improved tolerance to physical and psychological stress, cortisol suppression, and a simultaneous elevation of testosterone (21).
Sleep extension may also be an important strategic variable for implementation during predetermined overreaching phases of training (22). Since voluminous and intensive training carries a significant fatigue cost, the recovery requirements of the athlete increases concomitantly. Thus the implementation of sleep extension as a precautionary measure to both preserve performance and prevent injury may yield a protective effect.
Immune function is also a highly relevant subject regarding sport performance. Exceedingly high physical demands placed on the body through strenuous training requires a concomitant increase in recovery requirements. Thus an inability to recover sufficiently may not only jeopardize training performance but may also increase susceptibility to common illnesses (23). Although direct evidence is lacking “experimental studies have demonstrated that sleep deprivation results in poorer immune function, such as reduced natural killer cell activity, suppressed interleukin-2 production, and increased levels of circulating proinflammatory cytokines” (23). Thus blunted immune function resulting from sleep deprivation may increase the risk of illness which can temporarily sideline athletic development.
Consumption of stimulants such as caffeine are common, with approximately 85% of the US population consuming at least one caffeinated beverage per day (24). Caffeine is also widely used in various sports to enhance athletic performance (25)(26)(27)(28). However for some, caffeine consumption can have anxiogenic effects (causing anxiety). Caffeine has psychostimulant properties that may induce anxiety, research suggests this is largely due to the interaction between A1 and A2A adenosine receptors and other transmitter systems (29)(30). These adenosine receptors are involved in the regulation of sleep, arousal and cognition (31).
Because of its effects on the adenosine system caffeine can be an effective resource for managing many of the downstream effects of sleep deprivation (31). However, individual tolerance and effects of caffeine ingestion can vary greatly. Genetic and environmental factors mediate the effects and half-life of caffeine in the system (31). Individuals who are less resilient to stress were more sensitive to sleep disturbances including caffeine consumption (32). Essentially, what the research reflects is that individuals who exhibit disturbed sleep may benefit from a reduction or elimination of stimulants such as caffeine. So if recovery optimization is a priority, this may be a point worth considering. While on the Revive Stronger podcast, Greg Potter Phd, Msc offered sound recommendations for caffeine consumption at 2mg/kg of bodyweight and to consume at least nine hours prior to sleeping (33).
Our circadian rhythm relies on the suprachiasmatic nucleus which connects the retina and the pineal gland. The pineal gland secretes melatonin and is highly sensitive to light (especially blue light) which suppresses melatonin secretion (34). Circadian rhythm operates on a 24 hour cycle determined by exposure to light. However because of technology and the constant exposure to light, desynchronization occurs between our biological clock and the natural environmental rhythm. This desynchronization was described in a 2016 paper as follows, “Light blocks the release of NA by sympathetic terminal nerves of the pineal gland, and as result it neutralizes the activity of N-acetyltransferase (NAT), the key enzyme for synthesis of the hormone which results in a profound inhibition of melatonin synthesis” (34).
Blue light exposure through mobile device and personal computers continues to rise. This exposure delays the natural circadian phase which blunts signalling for melatonin secretion and sleep regulation. One study found that plasma concentration of melatonin was significantly reduced following light exposure but returned to baseline 1 hour after exposure ended (35). However, due to intra-individual variability I would recommend limiting light exposure two hours prior to going to bed.
Our chronobiology describes the natural rhythms of our biology and environment. Lifestyle plays a crucial role in proper sleep habituation. Our bodies respond well to patterns, especially with regard to chronobiology. Thus irregular sleep patterns such as shift work can cause reduced alertness, increased risk of fatigue related accidents, decreased motivation etc (36). However, these drawbacks are not limited to shift work and can effect individuals who maintain irregular sleep schedules and habits. Habituation plays an important role in ensuring consistent high quality sleep and thus recovery is maintained. The national institute of health established the following guidelines to help ensure a good nights sleep (37):
- Set a schedule – go to bed and wake up at the same time each day.
- Exercise 20 to 30 minutes a day but no later than a few hours before going to bed.
- Avoid caffeine and nicotine late in the day and alcoholic drinks before bed.
- Relax before bed – try a warm bath, reading, or another relaxing routine.
- Create a room for sleep – avoid bright lights and loud sounds, keep the room at a comfortable temperature, and don’t watch TV or have a computer in your bedroom.
- Don’t lie in bed awake. If you can’t get to sleep, do something else, like reading or listening to music, until you feel tired.
- See a doctor if you have a problem sleeping or if you feel unusually tired during the day.
A bi-phasic (2 phases) or polyphasic (3+ phases) approach to sleep is characterized by a fragmented sleep pattern. Interestingly enough many species have sleep patterns resembling a polyphasic structure (38). However in humans the subject is still a bit nebulous. With regard to individuals with sleep disorders, a fragmented approach to sleep may offer some substantial benefits (39). However, less research is available on multi-phase sleep patterns in healthy populations, and even less exists within the context of athletic performance.
A 1991 paper by Bonnet found napping improved vigilance, addition, logical reasoning, and alertness (40). Sallinen et al observed naps reduced number of lapses on reaction time task and reduced physiological sleepiness and subjective fatigue (41). This is an alignment with various other studies also reporting similar improvements in cognitive performance (42)(43)(44). However within the context of athletic performance, there appear to be a few key benefits to napping for some athletes.
To quote a 2017 paper by Simpson et al. “Insufficient sleep among athletes may be due to scheduling constraints and the low priority of sleep relative to other training demands, as well as a lack of awareness of the role of sleep in optimizing athletic performance” (45). Athletes have also been observed to sleep less and have lower quality sleep when compared with non-athlete populations (46)(19)(23)(47). So, from a basic valuation of total daily sleep, the potential of a bi-phasic approach to improved recovery becomes more apparent. This may be especially applicable for athletes who struggle with sleep quality and duration in spite of following the NIH sleep hygiene guidelines.
Since total daily sleep is a decent proxy for recovery and athletic performance, a bi-phasic approach may be an effective adjunct to the typical monophasic sleep pattern of most athletes. The research on napping however has been somewhat conflicting in regard to the time of day and duration individuals should establish an additional block of sleep.
A 2005 paper by Hayashi et al. compared the recuperative effect of naps and found “In the No-nap condition, subjective mood and performance deteriorated, and Slow eye movements increased during mid-afternoon, suggesting that the post-lunch dip occurred”(48). Research by Tucker et al. showed that naps improve memory which seems to be related to the sleep architecture although how the architecture of naps vs nocturnal sleep differ is still unclear (49).
A 2002 study found “a 10-min afternoon nap significantly improved subjective alertness, fatigue and [cognitive] performance” (50). Longer duration naps (+30min) also have significant benefit, however researchers often observe a delay in performance benefits due to sleep inertia (50). Sleep inertia is a physiological state of impaired cognitive and sensory-motor performance that is present immediately after awakening. Sleep inertia is generally only an issue with longer duration naps and is influenced by what stage of sleep you are in upon waking. However if the total amount of nocturnal sleep an athlete routinely gets is insufficient, implementation of longer naps would be beneficial by bolstering the total daily sleep duration. Intelligent scheduling of naps can mitigate most or all of the potential cognitive impairment due to post nap sleep inertia while allowing them to reap the benefits of increased total daily sleep.
The Role Of Nutrition In Recovery And Athletic Performance:
Sports nutrition is an ever advancing field of research. According to the ISSN “In the year 2017 alone, 2082 articles were published under the key words sport nutrition” (51). When structuring a nutritional approach to optimize athletic performance, energy intake should be the primary focus (52)(53)(54). Energy balance is the relationship between energy intake (via food) and expenditure (via metabolism, physical activity etc) (55). These energy requirements may change depending on the type of training an athlete is involved in, with higher volumes and intensities requiring a concomitant increase in calories to sustain performance and mitigate fluctuations in bodyweight (51).
Self reporting of energy intake is known to have varying degrees of accuracy, with the largest inaccuracies coming from obese adolescents and the smallest inaccuracies observed in lean adults (56)(57). Therefore it’s important to implement some form of objective monitoring system to ensure optimal energy intake and timing is sustained. Energy requirements are determined by calculating resting metabolic rate (RMR) and energy expenditure through daily activity. This is known as total daily energy expenditure (TDEE). There are numerous calculations which can be used to estimate energy intake with a relative degree of accuracy some of which you can find here (58). It’s important to note that no equation is 100% accurate, but depending on the athletes goals (ie. gain, lose or maintain bodyweight) monitoring bodyweight will inform whether the equation overestimated or underestimated their energy intake.
A common recourse is the utilization of technology in the form of diet apps to track tangible data which informs future dietary decisions. The accuracy of such apps are variable as found in a 2018 paper by Griffiths et al (59). Although, since any inaccuracy of the app will be more or less constant you can still identify trends over time and get the desired outcome. As far as apps go, my personal preference is My Fitness Pal which is does a good all around job (60).
If you decide not to use an app, and you are uncomfortable using a more complicated equation you can simply multiply your bodyweight in kilograms by 25-40. For example, if an athlete weighs 100kg you can just multiply 100 by a number between 25-40 to yield a caloric total. I want to reiterate that the number you choose is not overly important because in most cases you will need to adjust your calories anyway based on how your bodyweight responds. This is just a starting point and it’s unlikely to have a negative impact on your performance.
Research estimates the failure rate of dietary interventions to be roughly 85%, identifying lack of adherence as a key moderator (61). Knowing this we can infer that a theoretically optimized program may not actually be optimal for a particular individual in a given circumstance. This is an important factor that is sometimes neglected in spite of various inter-individual differences in lifestyle, genetics, personal preference etc. Therefore it’s prudent to adapt dietary interventions to each athlete rather than enforce a preferred method that may be inappropriate for the athletes circumstance or predilections.
Macronutrients are the bodies primary energy sources and are comprised of protein, carbohydrates, fats and alcohol (51). Since alcohol is not entirely relevant to the discussion of recovery it will not be explored further. Each macronutrient plays an integral role for both health and athletic performance.
Carbohydrates are the bodies preferred energy substrate, and are especially relevant in athletic performance (62)(63)(64). Carbohydrates serve various purposes including glycogen repletion, ATP production, and is required by the brain for several functions (63). Several studies have demonstrated the significance of carbohydrates in athletic performance specifically with regard to the muscles ability to contract with high force (65)(66)(67). One paper found that glycolysis generates roughly 80% of the ATP requirements during high intensity resistance exercise (68). A 1999 paper by Leveritt and colleagues looked at the effects of carbohydrate restriction on performance and found “Squat repetitions were significantly reduced after the carbohydrate restriction program” (69). A 2019 paper found “In the literature, recommendations for strength sports, which includes bodybuilding, intakes of 4–7 g/kg/day and 5–6 g/kg have been proposed” (70).
Protein turnover in skeletal muscle refers to the rate of protein breakdown in relation to the rate of protein synthesis (71). When the rate of protein synthesis exceeds the rate of protein breakdown the net result is muscle growth. Conversely, if protein breakdown outpaces the rate of protein synthesis muscle degradation occurs. Sufficient protein intake is critical for maintenance of muscle mass and recovery from strenuous bouts of resistance training. Recommendations by Helms et al suggest a daily protein intake of 1.6-2.2g/kg of bodyweight (70). So if an athlete weighs 100kg their optimal daily protein intake would be somewhere between 160-220g.
The quantity of protein during a single feeding is also relevant. Muscle protein synthesis (MPS) refers to the rate by which proteins can effectively be synthesized into muscle. Common recommendations for maximizing the muscle protein synthetic response is 20g (72)(73). However post resistance training researchers have found “ingestion of 40g whey protein following whole‐body resistance exercise stimulates a greater MPS response than 20g in young resistance‐trained men” (74). There also appears to be a refractory period at which time MPS can not be maximally stimulated (75). Therefore to optimize nutrient partitioning for muscle repair and growth it is recommended that protein feedings consist of 40g servings. It should be mentioned however that protein intakes as high as 70g per serving have shown to be beneficial, not because it further increases MPS but because it impedes muscle protein breakdown MPB (76). Certain populations (such as the elderly) require higher protein intakes (1.2-2.0g/kg/day) due to a decreased sensitivity in MPS response (77)(78).
A paper by Schoenfeld and colleagues found that protein intake per serving should be roughly 0.4-0.6g/kg and should be spread across a minimum of four meals per day (79). This would ensure you meet the minimum recommended target of 1.6g/kg of protein consumed per day. Meals should be spaced no less than three hours apart to minimize protein consumption during the refractory period after MPS stimulation (75).
The post workout anabolic window is a period post resistance exercise where the MPS response is far more sensitive. Subsequent discussion about the duration and effect size of this window has been conflicting. A 2018 paper by Schoenfeld an colleagues explored this topic and determined that the window is not limited to 30 minutes as is commonly believed. Rather the benefits of increased sensitivity appear to remain 24 hours post workout (80). This increase is not a fixed rate and diminishes in strength over time, therefore consumption of protein should occur roughly within 4-6 hours post workout. Although if it is available to you, there is no downside to earlier consumption of protein following a bout of resistance training.
Dr. Schoenfeld also found that the benefits of the post workout anabolic window depends largely on pre-workout nutrition “Thus, provided that such a meal [of sufficient protein content] is consumed within about 3 to 4 hours prior to a workout (or possibly even longer, depending on the size of the meal), the need for immediate post-exercise nutrient consumption is abated” (80)(81). It should also be mentioned that although the post workout window does appear to have benefits, total daily protein intake is by far the most important factor (80). So prioritizing nutrient timing at the expense of 24hr protein consumption is a poor trade off. Additionally, if an individual struggles to meet their daily protein requirements through food alone a protein supplement is a viable alternative (with the most bioavailable source being whey protein).
Fats are essential nutrients for health and play an important role in various metabolic functions. However with regard to athletic performance their utility is more contentious with research showing conflicting results (82)(83). Impeded sprint performance has been recorded following a low carbohydrate high fat diet (LCHF) (84). Cycling performance was preserved better through high carbohydrate intervention than the low carbohydrate control (85).
When looking at the entire body of literature on LCHF diets and athletic performance the results do not appear promising. While in some circumstances performance outcomes are comparable to high carbohydrate controls, other research reports performance degradation. Which is why in my opinion it seems counterintuitive to pursue a dietary approach that at best may yield similar results and at worst, impede performance. Therefore recommendations on fat intake as laid out by the American College of Sports Medicine are approximately 0.5-1.5g/kg/day (86). It’s also relevant to point out that meals in close proximity to a bout of resistance training should contain minimal or no fat. Fat requires a longer digestive period than protein and carbohydrates, so consumption of protein and carbohydrates exclusively within the pre/post workout window is ideal.
Stress Management, Recovery And Athletic Performance:
Stress is a critical factor to address when an athlete is attempting to optimize their recovery. Therefore it’s pertinent to understand the role of stress and its various influences and potential outcomes. The stress response system is a complex network of central neural and peripheral neuroendocrine responses, the purpose of which is to prime an organism to effectively manage fight or flight responses when a threat is perceived (87). There is significant inter-individual variability in stress response that are mediated by various psychological, environmental and genetic factors.
The genetic influence on stress is significant. One such influence is phenotypic plasticity. A phenotype is the composition of an individuals observable characteristics such as their appearance, development and behaviour, and is determined by genetics and environmental influences on these genes (87). Perceived environmental threats to survival or well being trigger a cascade of complex reactions that alter various physiological functions. As one paper pointed out “Although these neurobiological responses are protective and essential in acutely stressful conditions, they can become themselves pathogenic when persistently activated under circumstances of chronic or overwhelming stress and adversity” (87).
There is significant inter-individual variation with regard to their response to stress. While some athletes may be hyper-reactive others may have a hypo-reactive response. Therefore if two individuals are exposed to an identical stress (high stress work environment, loss of sleep, strenuous physical activity etc.) the neurophysiological response may vary significantly. Where one individual may have only a mild or even no response, the next may experience a very robust stress response. Therefore, an accurate evaluation of an athletes existing stressors and the associated impact is important in effective stress management for optimized recovery.
Interestingly enough, research has found an increased resiliency to stress in athletes not present in un-athletic populations (88). It’s common knowledge that physical activity has a significant impact on reducing all cause mortality (89)(90)(91). However recent research has demonstrated that there may in fact be an independent conditioning process related to exercise. As one paper noted “we found sufficient supportive data to propose the hypothesis of the occurrence of intrinsic and independent “hormonal conditioning” process in athletes, located centrally in the hypothalamus-pituitary axis, similar to those observed in the cardiovascular system and muscle tissue” (88). These findings also suggest that the increased stress tolerance adaptation to exercise is not limited to athletic endeavours and likely impacts general stressors as well (ie. life, work, financial etc).
Therefore, addressing lifestyle stress is not based on a single assessment but rather an ongoing conversation that influences decisions on program design and lifestyle management. This brings us to the subject of adherence. Since the success of any athletic or dietary intervention is predicated on the adherence rate of the athlete, the athletes lifestyle must be considered prior to program development. This bottom up approach to training may offer some additional insights to the athletes level of physical preparedness. For instance it has been observed that athletic performance declines when under psychological stress (92). Thus if an athlete is entering a period of important examinations at school, it may be necessary to temporarily decrease intensity or workload. In this case theoretical optimization may be trumped by a reactive approach to training which can account for such lifestyle adjustments and thus manage stress effectively to preserve performance.
T others program design is the last place I look when addressing an athletes inability to recover. The rationale for this approach however is simple, I want to identify the causal factor(s) of their inability to recover. In most cases I have found lifestyle to be the primary causes. And once addressed, their recovery is sufficient to continue progressing without altering the program. However, if an athlete is not recovering due to lifestyle factors their adaptive threshold has not changed. For example, hypothetically speaking if an athlete requires 12 sets of squats per week in order to create a sufficient stimulus for progression, reducing volume will reduce fatigue but they will see no positive adaptations from the change. However, if we improve the lifestyle factors that are impeding their recovery we can maintain the 12 weekly set volume while allowing the athlete to recover for subsequent training sessions. But the reverse is also true, if the athlete has done a good job managing the various factors outside of training and is still unable to recover it’s clear the program is the issue and adjustments must be made.
General Adaptation Syndrome (GAS) is a principle that provides a framework for understanding the relationship between stress, adaptation and fatigue (93). It has had a large influence on the concept of periodization in general and has been depicted in various ways. One such way is the Stimulus Recovery Adaptation curve (SRA) as depicted below.
The above diagram offers a visual representation of the general process of adaptation to training. The athlete introduces a stimulus (training session) which generates fatigue, and temporarily masks their physical fitness. Then as the athlete recovers their athletic ability exceeds their previous capabilities. However, if the athlete does not introduce a stimulus often enough (ie. working out once per month) we see degradation and eventually a return to baseline or below. Conversely if the stimulus is too large or too frequent it may not allow for sufficient recovery in time for the next training session (stimulus) (94). Therefore if this trend were to continue unchecked it may lead to overreaching.
This is a simplistic overview of how training stress impacts recovery and subsequent performance. The primary drivers of adaptation (and simultaneously fatigue) are volume and intensity, and the intentional manipulation of these variables is necessary to maintain a balance between fatigue and fitness (95). This is the primary reason coaches use deloads in their program design. During a deload a reduction of volume or intensity or both is implemented to decay fatigue and allow for maximal expression of strength. This period may be programmed, or it can be implemented reactively based on the athletes response to training. My personal preference is the latter since rather than relying on predictive measures it’s reactive in nature.
The relationship between volume and intensity is also vitally important, since too much of either or both can lead to performance degradation and possible injury. Volume and intensity have an inverse relationship and is depicted in the image below.
As intensity increases, volume must be down regulated or eventually the athletes recovery capacity will be exceeded. The challenging issue with regard to practical recommendations for program design are the significant inter-individual differences present. Volume, intensity, variation, time to peak, lifestyle etc all impact the structure and progression of the program. However, one piece of advice that comes from my own approach to training is determining the length of each training block. My approach to coaching is simplistic and has a relative amount of overlap with the reactive training systems approach of Mike Tuscher. I design a single week of training and then repeat it with weekly predetermined load progressions until my progress stalls. The time point where performance drops determines the length of a training cycle. So if I get a decrease in performance on week six, my training blocks will run five weeks long and on the sixth week I will deload. But regardless of which training approach you use, the implementation of deloads or periods of reduced volume and intensity are critical for long term athletic development and injury prevention.
One of the common themes in strength training is selecting volumes and intensities that are well beyond the capability of the athletes. This is also seen in various gym cultures where the “no days off” mentality persists. In some cases this is seen in training to muscular failure. Although this method has a valuable place in bodybuilding, its utility in strength training is questionable. The reason is due to the fatigue cost associated true failure training. A 2015 systematic review and meta analysis assessing the value of training to failure for strength development found “it seems unnecessary to perform failure training to maximize muscular strength; however, if incorporated into a program, training to failure should be performed sparingly to limit the risks of injuries and overtraining” (96).
A 2004 meta analysis found a dose response relationship between volume, intensity and strength progression by which a spectrum of possible intensities and volumes exist to progress in strength. Going too far beyond these end ranges is unlikely to elicit maximal strength gains with the upper limit being roughly 85% 1RM (97). Anecdotally it is very rare to hear of top tier athletes training to muscular failure. Since one of the mechanisms of injury is loading a tissue beyond its functional capacity, the implementation of failure training for strength development unnecessarily risk the athletes health (98). Additionally the high neurophysiological cost of training to failure with heavy loads substantially increases the fatigue cost which may overshadow any potential benefits. Therefore as a regular strategy, failure training is not recommended if maximizing strength is the goal.
The Effect Of NSAID’s On Athletic Performance
NSAID stands for non-steroidal anti inflammatory drugs. Some examples of which are aspirin, ibuprofen, Cambia, Cataflam, Voltaren-XR, Zipsor, Zorvolex etc. They are often used in athletic performance for analgesic or recovery purposes. However, the research demonstrating these benefits is scant and often conflicting. A paper titled Prophylactic Use of NSAIDs by Athletes: A Risk/Benefit Assessment found “Scientific evidence for such benefits is sparse, and athlete rationale for using prophylactic NSAIDs for their preemptive analgesic and anti-inflammatory effects appears at odds with current understanding of the underlying pathology of many sports related injuries” (98).
NSAID’s appear to alter the response to resistance training through inhibition of the prostaglandin system and decreased satellite cell proliferation and myonuclear domain. This system plays a role in mediating inflammation and researchers have observed in both animal and human models that NSAID consumption blunts protein metabolism (99)(100)(101). However when looking at the totality of evidence it’s still unclear if NSAID’s do in fact impose a negative effect on strength and hypertrophy (102)(103). This could at least in part be due to a lack of standardization of dosages across studies (104). At the moment the research doesn’t suggest a clear benefit to the use of NSAID’s and has in some instances shown adaptive decrements. So as a primary recovery strategy the data just doesn’t support their efficacy.
The Effect Of Massage And Cupping On Recovery And Athletic Performance
The primary rationales for utilizing massage for improved athletic performance are reducing DOM’s (delayed onset muscle soreness), decreasing recovery time, improved blood flow to the muscles, improving performance, removal of metabolic byproducts (ie. lactate and associated hydrogen ions etc), and improved subjective sense of recovery. However, recently many of the purported benefits have been called into question. In spite of this, many individuals still seek out massage therapists to support their athletic recovery.
A 2000 paper examined the effects of sports massage on various metrics of athletic performance and recovery. The researchers found elevated blood lactate concentrations in the massage group, with no observable differences between the passive rest condition on blood glucose and heart rate (105). This runs contrary to the common attribution of increased clearing of metabolic byproducts resulting from massage. However several studies have shown massage does not in fact affect either arterial or venus blood flow (106)(107)(108). And while some papers have found reductions in lactate concentration post massage, a simple active cool down has been shown to outperform massage in this regard (109)(110).
This same 2000 study measured punching force of boxers and found during subsequent rounds punching force decreased in both groups demonstrating the massage intervention was unsuccessful at preventing performance decrements during repeated bouts of training (105). This is not a stand alone finding either with other research demonstrating reductions in muscular strength following a pre-workout massage (111). It should be mentioned that reductions in strength are transient and may result from close proximity prior to training. However, outside of this specific circumstance massage would yield no detrimental effects on force output but would also have no positive impact.
Regarding the impact of massage on DOM’s, there has been conflicting findings. While some research shows marked improvements, others show no change at all (112)(113)(114). The reduction in DOM’s likely has a large psychological component to it. The very act of seeing a therapist and receiving treatment can trigger a cascade of psychophysiological effects including an up regulation of parasympathetic activity following treatment (115)(116). Therefore, massage does not appear to have an impact on recovery or performance outside of the psychological benefits associated with treatment/relaxation.
Cupping is another therapeutic technique that is often treated as a primary rather than an adjunctive therapy. However the research on cupping and various other eastern therapeutic practices are highly questionable. A 2011 systematic review looking at the efficacy of cupping as a treatment protocol found “The likelihood of inherent bias in the studies was assessed based on the description of randomization, blinding, withdrawals and allocation concealment. Four of the seven included trials [7–9, 13] had a high risk of bias. Low-quality trials are more likely to overestimate the effect size [14]. Three trials employed allocation concealment [10–12]…. None of the studies used a power calculation, and sample sizes were usually small. In addition, four of the RCTs [7–9, 13] failed to report details about ethical approval. Details of drop-outs and withdrawals were described in two trials [10, 11] and the other RCTs did not report this information which can lead to exclusion or attrition bias. Thus the reliability of the evidence presented here is clearly limited” (117).
Interestingly enough a substantial portion of the research supporting the efficacy of cupping and acupuncture come from Russia and China. Additionally no trial published in China or Russia has ever found a treatment to be ineffective (118). Although this sounds promising, in reality it’s a glaring red flag. The sheer statistical improbability of such uniform findings for a therapeutic modality in which the potential mechanisms of benefit are not even well understood is staggering. Several studies have been found to create design features that are highly likely to generate false positives in their outcomes (119). Therefore at the moment the implementation of cupping to reduce pain and/or aid in recovery is unsupported by the literature.
Effects Of Foam Rolling On Recovery And Athletic Performance
Much like massage, foam rolling or self myofascial release techniques (SMR) are widespread. Due to their low cost and relative ease of access several athletes and coaches implement their use for various intended purposes. The majority of the research has found that extended periods of foam rolling pre-exercise may inhibit certain athletic qualities such as maximal strength and jump performance (120). This appears to be at least in part due to blunted neural signalling, decreased motor unit recruitment and/or increased parasympathetic activity following prolonged bouts of foam rolling (ie. five minutes or more) (121).
While improvements in sprint performance have been documented results were shown to be at the lowest level of significance and remain questionable (120). Other research still shows no significant effects on sprint performance with pre-performance foam rolling (122). It has been proposed that any benefits to performance or recovery result from placebo effects and not foam rolling (123). As one paper found “it remains questionable whether the average post-rolling-induced enhancements of performance recovery were really due to a true physiological effect of FR or whether the placebo effect or methodological aspects contaminated these results” (120). Therefore foam rolling has not demonstrated positive results in relation to recovery and subsequent athletic performance.
Effects Of Heat And Cold Therapy On Recovery And Athletic Performance
Heat and cold exposure has a wide range of outcome depending on the grade of the exposure. It’s not uncommon for athletes to utilize saunas and cold water emersion to aid in recovery, improve athletic performance or as a relaxation tool. Internal body temperature correlates quite closely with exercise tolerance, with exhaustion typically occurring at 39.4ºC (124). During elevated internal body temperature researchers have observed increased cardiac output, decreased ability to buffer lactate and other metabolic byproducts, and compromised oxygen transport to muscles etc (124).
The utilization of saunas can be effective, however if implemented directly after training can potentially carry some downsides. Elevated internal body temperature has been shown to increase cell swelling and sympathetic activity, prolonging your stress state and blunting recovery and increasing fatigue (125). Therefore it’s recommended that saunas be used a few hours post training to prevent this occurrence. Additionally, heat exposure should remain between 10-30 minutes in duration to prevent dehydration, heat exhaustion and excessive fatigue (126).
The physical benefits of heat exposure in general are several. Vasodilation increases blood flow and nutrient transport including amino acids for protein synthesis into the muscles. Increased blood flow also helps clear out metabolic byproducts generated from hard training to aid in recovery. Sauna also has relaxation and analgesic (pain relief) effects in decreasing DOM’s, and improving cellular regeneration (127). However, the buildup of metabolites in the body is an independent stimulus for hypertrophy and other physiological adaptations. Therefore, removal of these byproducts diminishes the adaptive potential of the training session.
Currently there doesn’t appear to be any difference in the efficacy between various implementation strategies of cold therapy, so ice packs, cold water emersion, chriochamber etc all work roughly the same. With the primary difference being access and the ability to treat globally vs locally (ie. ice packs vs full body cold water emersion). Cold water therapy has been demonstrated to reduce efflux of creatine kinase (a metabolic byproduct of rigorous exercise), improve muscle power and decrease inflammation (128). The hydrostatic pressure of cold water emersion has analgesic effects in reducing delayed onset muscle soreness likely through its interaction with nociceptor signalling (128). This approach would ideally be implemented immediately after training for bouts of 15-20 minutes when inflammatory makers are at their highest.
Contrast baths are also used to extract the benefits of both hot and cold exposure. Exposures of 10-30 minutes of total time in hot and cold at 0-90 minutes post training are recommended. However because heat increases fatigue and cold decreases fatigue exact recommendations are still unclear. There also doesn’t seem to be a difference between which you start and/or finish with (ie. hot or cold).
Similar to heat exposure, the implementation of cold therapy blunts some of the metabolic signalling directing adaptations. It should also be mentioned that the effect size that heat exposure and cold therapy have on recovery (although not negligible) is quite small. As such beginner and intermediate athletes should not prioritize these therapies because they are further down the hierarchy than sleep, nutrition, training program, lifestyle etc.
Effects Of Creatine On Recovery And Athletic Performance
Creatine is a popular supplement that actually has a large body of evidence in support of its use. High intensity exercise in general relies on creatine and phosphorylcreatine to aid in ATP resynthesis (129). A 2012 paper found “High-intensity exercise can result in up to a 1,000-fold increase in the rate of ATP demand compared to that at rest” (130). Therefore the rate of ATP availability is a critical factor in exercise performance at high intensities.
The primary source of dietary creatine comes from consumption of fish and meats, with roughly 95% of creatine stored in skeletal muscle (131). However, various forms of creatine are available in supplement form with creatine monohydrate being the most efficacious (132). Creatine aids in enhanced repletion of muscle glycogen and phosphorylcreatine, and may also modulate various growth factors like IGF-1 (129). Creatine has also been shown to increase the number of satellite cells and myonuclei in skeletal muscle, and may also provide a resiliency to fatigue by buffering metabolic byproducts like hydrogen ions (133)(134)(135). In this regard creatine is effective at increasing recovery ability both within session and between subsequent training sessions. Recommendations made by the ISSN on creatine supplementation are 3-5g consumed per day, with my personal stance preferencing 5g per day (136).
Effects Of Vitamin Supplementation On Recovery And Athletic Performance
Vitamins directly or indirectly regulate various physiological functions, therefore deficiencies may in fact lead to performance decrements. However, this is often a point of contention because the larger body of research has not demonstrated any benefit to vitamin supplementation on athletic performance (137)(138). These findings are reflective that vitamin requirements are often met by the dietary practices of the athlete. Therefore, outside of correcting a specific vitamin deficiency the use if vitamin supplements will not yield additional benefits to athletic performance.
Closing Comments
I’d like to take this time to highlight the over arching theme of this article. Although several strategies exist to optimize recovery, individual circumstance and the magnitude of impact should be the primary consideration. Sleep, nutrition, program design and life stressors make up the vast majority of effective recovery strategies. However because they are not flashy and do not sound overly sciencey they get overlooked in favour of more complex and exciting approaches. However, the fundamental tenants of training are always going to produce the most meaningful results. So start there and don’t rush to adopt new strategies, especially if they compromise the primary focal points of recovery. Good luck.
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