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The short answer is the improvement in basic science research in Ayurveda before proceeding to clinical research and trials.In its present form, Ayurveda is somewhat like giving“an unknown dose of an ill-defined drug, of unknown effectiveness and unknown safety”What are the differences between testing modern drugs and Ayurvedic medicines?Hundreds of modern drugs are manufactured from plant sources including some anti-cancer agents. So it is not quite correct to say that modern drugs are artificially produced chemicals. But one can't term Vincristine (cancer drug) or Atropine (an anticholinergic drug) as herbal products of Catharanthus roseus and Atropa belladonna. [1]Testing of drugs only comes in when the desired molecule is known. In Ayurveda, all evidence is gathered from a retrospective approach and the tested material does not contain any known chemical in any known specified dosage. It is a mixture of 100s of ingredients whose chemical composition is not known and whose recipes were set in stone 2500 years ago and can't be apparently modified because one cannot insult the wisdom of our ancestors. It's efficacy or non-efficacy cannot be ascertained in a controlled environment because there is no one single chemical that is being tested at a time. That is why food standards are used to test Ayurveda because testing a particular chemical seems to be difficult, if not impossible, in Ayurveda.If a traditional medicine is found to have a beneficial and desired effect with the safety profile being acceptable and there is enough evidence that it works as it is supposed to- the medicine ceases to be a traditional drug and becomes a modern drug. There are scores of such traditional medicines becoming modern drugs. Whether it is a the Cinchona bark (from which the anti-malarial drug Quinine is extracted) curing malaria in the 18th century or the modern drug Artemisinin (derived from the chinese medicinal herb, Artemisia annua- Tu You You won the Nobel Prize in medicine in 2015 for this discovery and research) doing the same today- whenever a traditional drug has been found promising, it has been tested extensively via clinical trials to make the traditional medicines go mainstream.[2] [3]Basic science research is what brings new drugs to the consumer market. Research identifies the molecules that are useful in a particular disease or condition. Only then does the testing of modern drugs on animals and humans begin. This is the cardinal difference between testing of modern drugs and Ayurvedic drugs.Unless Ayurvedic practitioners and researchers come up with decent basic science research which are publish worthy with authentic data and then go on to publish in reputed peer reviewed journals like Nature or Lancet- all of their supposed “research” will be considered low quality. Clinical research is for confirming basic science research and not the other way round as Ayurvedic practitioners seem to be doing these days in the name of research.You can't say for example, “This seems to work so there must be some science to it” and create a weird theory to fit in the conflicting data. One usually needs the hypothesis first and then your experiments need to confirm the hypothesis. After one proves the hypothesis do scientists apply the hypothesis in the real world. This is how real science works.The modern drugs go through 4 phases of Clinical Trials[4]Phase 1 is to assess the safety profile of the drug being tested and its side effects. Involves a few healthy volunteers (<100) and needs several months to complete.Phase 2 - Efficacy and effectiveness of a drug is done here. This phase also determines the treating dosage and toxic levels. A placebo may also be used as a control arm. A few hundred healthy volunteers are required and this may take a few years to completePhase 3 is Randomized Controlled Trials (RCTs) where therapeutic dosage is given to a large sample of people suffering from a specific ailment or disease and comparing with a control arm which use the placebo in double-blind fashion so that both the patient nor the investigator knows who is getting the tested drug and who is getting the placebo. This eliminates bias. This typically takes several years to complete. RCTs is the most robust form of evidence that a drug works. No Ayurvedic or Homeopathic drug has cleared this phase till date.Phase 4 is when the drug goes into consumer market. Data is collected regarding long-term effects of the new drug, over longer durations and on larger number of people than could be achieved via clinical trials. Many drugs have been banned after reaching the consumer market if the side effects did not make the benefit-to-cost ratio favourable to the general public. The drugs were withdrawn fully or partially depending on its usage eg: Rofecoxib or Thalidomide.At every phase, the investigators and researchers publish several scientific papers and review articles in reputed peer reviewed journals to support the use of a particular drug in a particular disease /ailment along with the side effects of the drugs that need to be factored in. Every drug has a lot of this information especially about adverse effects mentioned on the drug’s packaging. So the process is very transparent for all to know.If you apply these principles to Ayurveda one can see why this is not really possible without proper basic science research first. If curcumin (present in Turmeric) is the active ingredient which has anti-cancer properties, you can't really test a recipe containing 100s of ingredients including turmeric without having a confounding bias in that study. It is curcumin only which needs to be extracted, studied and tested further.Low quality/ non-existent basic science research leads to low quality clinical research. Moreover a lot of “Ayurvedic research” is shrouded in mystery with many of their theses filled with fantastical tales and engaging anecdotes to cater to the lowest common denominator in intelligence. Basically dumbing down science by oversimplification so that they can sell the drugs.Levels of evidenceThere are various levels of evidence in medical research depending on the strength of the evidence and the bias in the data collection and statistics. Level I being the best and Level V being the leastAs you can see in the above table, anecdotal evidence (expert opinion) though useful many times to discover new drugs- is the poorest form of evidence at level V.What should the Indian government be doing?The present Indian government and the AYUSH & health ministry in particular are using the current favorable political climate to make outrageous claims which have no logical basis like-AIDS, cancer can be cured by Ayurveda, says Union MinisterAyurvedic cure for cancer not far away: Ayush Shripad Naik - Times of IndiaYoga can cure cancer, govt may have proof in a year: Minister, AYUSH Shripad NaikWant to cure cancer? Research ayurveda, yoga and homeopathy, says ministerThe AYUSH website mentions various “research projects” in progress. These seem to be just placeholders which will show no further changes and no new information will come out in the years to come. There will be just more outrageous claims than any real hard evidence. The only way to know if any of their “research projects” are significant is whether any of their research is published in reputed indexed international journals. This is a good barometer because it is not easy to publish in such journals without having concrete data supporting their conclusions. Unless that happens it is difficult to believe anything that the dubious investigators will say. Even the papers about Ayurvedic drugs by Ayurvedic practitioners that I have read till date are of such poor quality that it is with difficulty that they qualify even for level V evidence.Basic science research needs money and that should be funded by the Ayurvedic medicine manufacturing companies. Many of these Ayurvedic companies have annual revenues of Rs. 5000–10,000 crores[5][6][7] They could easily afford to spend on good quality basic science research but they are not forced to by the government in the same way modern drugs are subjected to extreme scrutiny. This needs to change if Ayurvedic researchers want to be taken seriously. In fact the researchers should advocate for more basic science research and force these Ayurvedic drug companies to invest in these research projects. Government should not spend public money to fund these non-existent or low quality studies.As long as the government is blind to the intricacies of modern medical research I don’t see anything improving much on the research front in Ayurveda. Unless Ayurvedic drugs are subjected to the same level of scrutiny that modern drugs are subjected to, Ayurveda will be viewed with skepticism.The least the government could do is to make sure that the Ayurvedic drugs sold in the Indian domestic markets at least undergo food safety requirements so that even if it does not have its intended effects, it may not kill anyone. At present any person can make Ayurvedic concoctions in their run down garage and sell it in the open market with outrageous claims of curing diseases - from AIDS to Cancer. These drugs are not even tested for safety-you can forget about cures, efficacy and consistency.Footnotes[1] These Drugs Come from Plants[2] Cinchona - Wikipedia[3] Artemisinin - Wikipedia[4] Overview of Clinical Trials[5] Patanjali Ayurved - Financial Report[6] http://www.himalyainternational.com/corporatre/agm2016/annual%20report%202016.pdf[7] Dabur North America, Dabur Chyawanprash, Chyawan Granules, Dabur USA

TL;DR - Yes and you should if you can and have time. The positive effects are many and include: increasing lifespan, increasing HGH (human growth hormone), increasing hypertrophy (muscle growth), increasing red blood cell count (and in turn, endurance, improved insulin sensitivity.As John points out below - drink a lot of water, so as to not become dehydrated.---So what sort of gains can you anticipate?One study demonstrated that a 30-minute sauna session two times a week for three weeks POST-workout increased the time that it took for study participants to run until exhaustion by 32% compared to baseline.4The Effects of Hyperthermic Conditioning on Muscle Hypertrophy (Growth)Exercise can induce muscular hypertrophy. Heat induces muscular hypertrophy. Both of these together synergize to induce hyper-hypertrophy.Here are a few of the basics of how muscle hypertrophy works: muscle hypertrophy involves both the increase in the size of muscle cells and, perhaps unsurprisingly, an accompanying increase in strength. Skeletal muscle cells do contain stem cells that are able to increase the number of muscle cells (called “hyperplasia”) but hypertrophy instead generally involves an increase in size rather than number.So what determines whether your muscle cells are growing or shrinking (atrophying)?A shift in the protein synthesis-to-degradation ratio…and an applied workload on the muscle tissue (of course). That’s it.At any given time your muscles are performing a balancing act between NEW protein synthesis and degradation of existing proteins. The important thing is your net protein synthesis, and not strictly the amount of new protein synthesis occurring. Protein degradation occurs both during muscle use and disuse. This is where hyperthermic conditioning shines: heat acclimation reduces the amount of protein degradation occurring and as a result it increases net protein synthesis and, thus muscle hypertrophy. Hyperthermic conditioning is known to increase muscle hypertrophy by increasing net protein synthesis through three important mechanisms:Induction of heat shock proteins. 89Robust induction of growth hormone.1Improved insulin sensitivity. 10...Heat Stress Triggers Heat Shock Proteins That Prevent Protein DegradationOxidative stress is a major source of protein degradation....Heat shock proteins (or HSPs), as the name implies, are induced by heat and are a prime example of hormesis. Intermittent exposure to heat induces a hormetic response (a protective stress response), which promotes the expression of a gene called heat shock factor 1 and subsequently HSPs involved in stress resistance.HSPs can prevent damage by directly scavenging free radicals and also by supporting cellular antioxidant capacity through its effects on maintaining glutathione.8,9HSPs can repair misfolded, damaged proteins thereby ensuring proteins have their proper structure and function.8,9Okay, let’s take a step back from the underlying mechanisms and look at the big picture of heat acclimation in the context of increasing muscle hypertrophy:It has been shown that a 30-minute intermittent hyperthermic treatment at 41°C (105.8°F) in rats induced a robust expression of heat shock proteins (including HSP32, HSP25, and HSP72) in muscle and, importantly, this correlated with 30% more muscle regrowth than a control group during the seven days subsequent to a week of immobilization.8Heat Stress Triggers A Massive Release of Growth Hormone...Another way in which hyperthermic conditioning can be used to increase anabolism is through a massive induction of growth hormone. 1415, 1 Many of the anabolic effects of growth hormone are primarily mediated by IGF-1, which is synthesized (mainly in the liver but also in skeletal muscle and other tissues) in response to growth hormone. There are two important mechanisms by which IGF-1 promotes the growth of skeletal muscle:It Increases protein synthesis via activation of the mTOR pathway. 16It decreases protein degradation via inhibition of the FOXO pathway.16...In fact, growth hormone administration to endurance athletes for four weeks has been shown to decrease muscle protein oxidation (a biomarker for oxidative stress) and degradation by 50%. 19My point is good news. You don’t need to take exogenous growth hormone. Sauna use can cause a robust release in growth hormone, which varies according to time, temperature, and frequency.1,15For example, two 20-minute sauna sessions at 80°C (176°F) separated by a 30-minute cooling period elevated growth hormone levels two-fold over baseline.1,15 Whereas, two 15-minute sauna sessions at 100°C (212°F) dry heat separated by a 30-minute cooling period resulted in a five-fold increase in growth hormone.1,15 However, what’s perhaps more amazing is that repeated exposure to whole-body, intermittent hyperthermia (hyperthermic conditioning) through sauna use has an even more profound effect on boosting growth hormone immediately afterward: two one-hour sauna sessions a day at 80°C (176°F) dry heat (okay, this is a bit extreme) for 7 days was shown to increase growth hormone by 16-fold on the third day.14 The growth hormone effects generally persist for a couple of hours post-sauna.1 It is also important to note that when hyperthermia and exercise are combined, they induce a synergistic increase in growth hormone. 20Increased Insulin SensitivityInsulin is an endocrine hormone that primarily regulates glucose homeostasis, particularly by promoting the uptake of glucose into muscle and adipose tissue. In addition, insulin also plays a role in protein metabolism, albeit to a lesser degree than IGF-1. Insulin regulates protein metabolism in skeletal muscle by the two following mechanisms:It increases protein synthesis by stimulating the uptake of amino acids (particularly BCAAs) into skeletal muscle. 21It decreases protein degradation through inhibition of the proteasome, which is a protein complex inside cells that is largely responsible for the degradation of most cellular proteins. 22In humans, there is more evidence indicating that the major anabolic effects of insulin on skeletal muscle are due to its inhibitory action on protein degradation....For this reason, hyperthermic conditioning may also lend itself to promoting muscle growth by improving insulin sensitivity and decreasing muscle protein catabolism. Intermittent hyperthermia has been demonstrated to reduce insulin resistance in an obese diabetic mouse model. Insulin resistant diabetic mice were subjected to 30 minutes of hyperthermic treatment, three times a week for twelve weeks.This resulted in a 31% decrease in insulin levels and a significant reduction in blood glucose levels, suggesting re-sensitization to insulin.10The hyperthermic treatment specifically targeted the skeletal muscle by increasing the expression of a type of transporter known as GLUT 4, which is responsible for the transporting of glucose into skeletal muscle from the bloodstream. Decreased glucose uptake by skeletal muscle is one of the mechanisms that leads to insulin resistance.-------------------------------------------------------------.:CONCLUSION:.To recap and drive the point home: acclimating your body to heat stress by intermittent whole-body hyperthermia via sauna use (“hyperthermic conditioning”) has been shown to:Enhance endurance by:Increasing nutrient delivery to muscles thereby reducing the depletion of glycogen stores.Reducing heart rate and reducing core temperature during workload.Increase muscle hypertrophy by preventing protein degradation through the following three means:Induction of heat shock proteins and a hormetic response (which has also been shown to increase longevity in lower organisms).Cause a massive release of growth hormone.Improving insulin sensitivity.Hyperthermic conditioning also has robust positive effects on the brain:Increases the storage and release of norepinephrine, which improves attention and focus.Increases prolactin, which causes your brain to function faster by enhancing myelination and helps to repair damaged neurons.Increases BDNF, which causes the growth of new brain cells, improves the ability for you to retain new information, and ameliorates certain types of depression and anxiety.Causes a robust increase in dynorphin, which results in your body becoming more sensitive to the ensuing endorphins.How long should you go in the Sauna? Well, the studies seem to show that hotter and longer is generally better, but realistic number for most people that should provide most of the benefits is:30-minute sauna session two times per week for three weeks POST-workout to start seeing the benefits (as hot as you can reasonably tolerate).Start slow - most people can't make it 30 minutes on the first few attempts. And that older guy in the corner who has been in there longer - don't try to keep up with him - he's probably been coming to the sauna for 20 years!Life is stressful.When you exercise, you are forcing your body to become more resilient to stress (somewhat paradoxically) through stress itself.Hyperthermic conditioning is a novel and possibly effective tool that can improve your resistance to the sort of stress associated with fitness pursuits as well as some that are not traditionally associated with fitness such as the protective effects of HSPs on various types of stress. That being said, deliberately applied physical stress, whether heat stress or ordinary exercise, is something that requires caution.You shouldn’t avoid it altogether, but you should use good common sense, not overwhelm yourself, and make sure to know your limits. (NOTE: you should not drink alcohol before or during sauna use as it increases the risk of death). Personal variation probably comes into play when finding your own sweet spot for building thermal tolerance while avoiding over-extending yourself.I believe that hyperthermic conditioning in general may be worth a closer look as a tool in the toolbox of athletes. Perhaps it can be used for much more than just relaxation?But no matter how enthusiastic you might be, remember:Heat responsibly and with someone else, never alone.Never heat yourself while drunk, and friends don’t let friends sauna drunk.If you are pregnant or have any medical condition, saunas are not for you. Speak with your doctor before starting this or any regimen involving physical stressors.Be careful, ladies and gents.ABOUT THE AUTHOR: Dr. Rhonda PatrickYou can find more video and writing from Dr. Rhonda Patrick at her website, FoundMyFitness.com.NOTE: This is a summary of a fantastically detailed article from Tim Ferriss' blog, which can be found in it's entirety here:Are Saunas the Next Big Performance-Enhancing “Drug”?References:Hannuksela, M. L. & Ellahham, S. Benefits and risks of sauna bathing. The American journal of medicine 110, 118-126 (2001). This is actually an important review article that covers some of the benefits of sauna use including the cardiovascular advantages and hormonal changes such as the boost in GH levels. I also like it because it covers some of the risks of alcohol use before or during the sauna. [↩]Ricardo J. S. Costa, M. J. C., Jonathan P. Moore & Neil P. Walsh. Heat acclimation responses of an ultra-endurance running group preparing for hot desert-based competition. European Journal of Sport Science, 1-11 (2011). The sample sizes in both studies referenced here and in #4 have small sample sizes but they are two independent studies that compliment each other. This study also reinforces the endurance enhancements in #5. [↩]King, D. S., Costill, D. L., Fink, W. J., Hargreaves, M. & Fielding, R. A. Muscle metabolism during exercise in the heat in unacclimatized and acclimatized humans. J Appl Physiol 59, 1350-1354 (1985). This study shows that glycogen utilization is decreased in runners after heat acclimation. The sample size is small but ref #7 (another small sample) is an independent study that shows the same effect. [↩]Scoon, G. S., Hopkins, W. G., Mayhew, S. & Cotter, J. D. Effect of post-exercise sauna bathing on the endurance performance of competitive male runners. Journal of science and medicine in sport / Sports Medicine Australia 10, 259-262, doi:10.1016/j.jsams.2006.06.009 (2007). This study shows the effect of preconditioning the body to heat stress by using a sauna for at least 30 min directly after after training session. While the study sample is small, other studies referenced in #2, #5 reinforce and compliment this. I also have some anecdotal data. I did some serious experimentation with the sauna a couple of years ago when I had access to a sauna. I would sit in the sauna for up to 60 min. until I pushed myself to extreme physical discomfort about 4-5 times a week. I substantially (and I know this is just anecdote) increased my running PRs. [↩]Michael N. Sawka, C. B. W., Kent B. Pandolf. Thermoregulatory Responses to Acute Exercise-Heat Stress and Heat Acclimation. Handbook of Physiology, Environmental Physiology (2011). This is a good review article that covers many of the mechanisms that underly the endurance enhancements as a consequence of heat acclimation. [↩]Garrett, A. T., Creasy, R., Rehrer, N. J., Patterson, M. J. & Cotter, J. D. Effectiveness of short-term heat acclimation for highly trained athletes. European journal of applied physiology 112, 1827-1837, doi:10.1007/s00421-011-2153-3 (2012). [↩]Kirwan, J. P. et al. Substrate utilization in leg muscle of men after heat acclimation. J Appl Physiol (1985) 63, 31-35 (1987). The findings in this study reinforce the data in ref #3. Both small sample sizes but multiple studies showing the same effect makes the argument stronger. [↩]Selsby, J. T. et al. Intermittent hyperthermia enhances skeletal muscle regrowth and attenuates oxidative damage following reloading. J Appl Physiol (1985) 102, 1702-1707, doi:10.1152/japplphysiol.00722.2006 (2007). This is an important paper because it shows that intermittent hyperthermia can enhance the regrowth of skeletal muscle in rats after disuse via induction of heat shock proteins. Having a quantitative way to non-invasively measure muscle mass in humans is difficult. Even though the experiment was done in rats (N=40) this is a good study because it also shows mechanism. [↩]Naito, H. et al. Heat stress attenuates skeletal muscle atrophy in hindlimb-unweighted rats. J Appl Physiol 88, 359-363 (2000). This study demonstrates that HSP induction by intermittent hyperthermia in rats can prevent muscle atrophy during muscle disuse. Again, this study was in rats but it shows mechanism has has a good sample size (N=40). [↩]Kokura, S. et al. Whole body hyperthermia improves obesity-induced insulin resistance in diabetic mice. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group 23, 259-265, doi:10.1080/02656730601176824 (2007). This study was done in mice (N=20) but it demonstrates a very important mechanistic finding that hyperthermia increases the expression of glucose transporters in skeletal muscle, thus improving insulin sensitivity. Exercise (which elevates core body temp.) is known to improve insulin sensitivity. This is a cool mechanism by which this can occur. [↩]Yamada, P. M., Amorim, F. T., Moseley, P., Robergs, R. & Schneider, S. M. Effect of heat acclimation on heat shock protein 72 and interleukin-10 in humans. J Appl Physiol (1985) 103, 1196-1204, doi:10.1152/japplphysiol.00242.2007 (2007). This study includes a relatively small human sample size (N=12) but it is a very important because it demonstrates that heat acclimation causes a higher induction of heat shock proteins upon later exercise. This is the fundamental concept behind hyperthermic conditioning. [↩]Moseley, P. L. Heat shock proteins and heat adaptation of the whole organism. J Appl Physiol (1985) 83, 1413-1417 (1997). This is a review article that explains some of the functions of HSPs and reinforces the data from reference #11 demonstrating that heat acclimation can increase the expression of HSPs. [↩]Kuennen, M. et al. Thermotolerance and heat acclimation may share a common mechanism in humans. American journal of physiology. Regulatory, integrative and comparative physiology 301, R524-533, doi:10.1152/ajpregu.00039.2011 (2011). This study is another small human sample size (N=8) but it reinforces the data from ref #11 because it demonstrates that some of the positive effects of heat acclimation are due to increased expression of HSPs. The study even shows specificity here by administering an HSP inhibitor, which ameliorates the positive effects of heat acclimation. [↩]Leppaluoto, J. et al. Endocrine effects of repeated sauna bathing. Acta physiologica Scandinavica 128, 467-470, doi:10.1111/j.1748-1716.1986.tb08000.x (1986). This is a very important study because it shows the profound hormonal responses to repeated sauna use in humans (N=17). By day 3, growth hormone increased 16-fold, highlighting the importance of hyperthermic conditioning. [↩]Kukkonen-Harjula, K. et al. Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath. European journal of applied physiology and occupational physiology 58, 543-550 (1989). Even though the human sample size in this study is small (N=8), it shows that varying temperatures and durations differentially affect hormones. Small sample or not, the fundamental chemical changes in this study are reinforced from the data referenced in #1 and #4. [↩]Velloso, C. P. Regulation of muscle mass by growth hormone and IGF-I. British journal of pharmacology 154, 557-568, doi:10.1038/bjp.2008.153 (2008). [↩]Coleman, M. E. et al. Myogenic vector expression of insulin-like growth factor I stimulates muscle cell differentiation and myofiber hypertrophy in transgenic mice. The Journal of biological chemistry 270, 12109-12116 (1995). In this study mice were engineered to constitutively express high levels of human IGF-1 in their muscle stem cells. This caused the proliferation and differentiation of myoblasts and caused muscle hypertrophy. [↩]Barton, E. R., Morris, L., Musaro, A., Rosenthal, N. & Sweeney, H. L. Muscle-specific expression of insulin-like growth factor I counters muscle decline in mdx mice. The Journal of cell biology 157, 137-148, doi:10.1083/jcb.200108071 (2002). [↩]Healy, M. L. et al. High dose growth hormone exerts an anabolic effect at rest and during exercise in endurance-trained athletes. The Journal of clinical endocrinology and metabolism 88, 5221-5226 (2003). [↩]Ftaiti, F. et al. Effect of hyperthermia and physical activity on circulating growth hormone. Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme 33, 880-887, doi:10.1139/H08-073 (2008). This study shows that hyperthermia SYNERGIZES with exercise to increase growth hormone levels in humans. So you can feel the burn from your routine and then jump immediately in the sauna for amplified effects. Again, small sample (N=8) but its conclusion is logical and intuitively follows the other studies. Anything that substantially increases core temperature should increase growth hormone and the effects should potentiate each other. [↩]Louard, R. J., Fryburg, D. A., Gelfand, R. A. & Barrett, E. J. Insulin sensitivity of protein and glucose metabolism in human forearm skeletal muscle. The Journal of clinical investigation 90, 2348-2354, doi:10.1172/JCI116124 (1992). This study demonstrated that insulin stimulated BCAA uptake in the forearm (post-absorptive and insulin infusion) The sample size in this human study was good (N=39). [↩]Lecker, S. H., Goldberg, A. L. & Mitch, W. E. Protein degradation by the ubiquitin-proteasome pathway in normal and disease states. Journal of the American Society of Nephrology : JASN 17, 1807-1819, doi:10.1681/ASN.2006010083 (2006). This is a review article that covers the mechanism by which insulin decreases protein degradation: proteasome inhibition. [↩]Chow, L. S. et al. Mechanism of insulin’s anabolic effect on muscle: measurements of muscle protein synthesis and breakdown using aminoacyl-tRNA and other surrogate measures. American journal of physiology. Endocrinology and metabolism 291, E729-736, doi:10.1152/ajpendo.00003.2006 (2006). This study used multiple different methods to measure protein synthesis and degradation in 18 humans after insulin infusion. The insulin levels were raised to physiologically relevant postprandial levels. [↩]Guillet, C., Masgrau, A., Walrand, S. & Boirie, Y. Impaired protein metabolism: interlinks between obesity, insulin resistance and inflammation. Obesity reviews : an official journal of the International Association for the Study of Obesity 13 Suppl 2, 51-57, doi:10.1111/j.1467-789X.2012.01037.x (2012). [↩]Selsby, J. T. & Dodd, S. L. Heat treatment reduces oxidative stress and protects muscle mass during immobilization. American journal of physiology. Regulatory, integrative and comparative physiology 289, R134-139, doi:10.1152/ajpregu.00497.2004 (2005). This study just reinforces and compliments the protective effect that HSPs have on muscle mass during disuse. It reinforces data referenced in #9. [↩]Nath, K. A. et al. Induction of heme oxygenase is a rapid, protective response in rhabdomyolysis in the rat. The Journal of clinical investigation 90, 267-270, doi:10.1172/JCI115847 (1992). This reference is relevant to the mechanism by which hyperthermic conditioning may protect against rhabdomyolysis: induction of HSP32. [↩]Wei, Q., Hill, W. D., Su, Y., Huang, S. & Dong, Z. Heme oxygenase-1 induction contributes to renoprotection by G-CSF during rhabdomyolysis-associated acute kidney injury. American journal of physiology. Renal physiology 301, F162-170, doi:10.1152/ajprenal.00438.2010 (2011). [↩]Khazaeli, A. A., Tatar, M., Pletcher, S. D. & Curtsinger, J. W. Heat-induced longevity extension in Drosophila. I. Heat treatment, mortality, and thermotolerance. The journals of gerontology. Series A, Biological sciences and medical sciences 52, B48-52 (1997). This reference, as well as the two immediate ones following, back up the notion that heat shock extends lifespan in lower organisms via HSP induction. [↩]Lithgow, G. J., White, T. M., Melov, S. & Johnson, T. E. Thermotolerance and extended life-span conferred by single-gene mutations and induced by thermal stress. Proceedings of the National Academy of Sciences of the United States of America 92, 7540-7544 (1995). [↩]Tatar, M., Khazaeli, A. A. & Curtsinger, J. W. Chaperoning extended life. Nature 390, 30, doi:10.1038/36237 (1997). [↩]Singh, R. et al. Anti-inflammatory heat shock protein 70 genes are positively associated with human survival. Current pharmaceutical design 16, 796-801 (2010). This study was a longitudinal cohort of a Denmark population (N=168) that found a slight increase in longevity (1 year) in females that had a polymorphism in the HSP70 gene that was associated with increased HSP expression upon heat stress. [↩]Yenari, M. A., Giffard, R. G., Sapolsky, R. M. & Steinberg, G. K. The neuroprotective potential of heat shock protein 70 (HSP70). Molecular medicine today 5, 525-531 (1999). [↩]Duveau, V., Arthaud, S., Serre, H., Rougier, A. & Le Gal La Salle, G. Transient hyperthermia protects against subsequent seizures and epilepsy-induced cell damage in the rat. Neurobiology of disease 19, 142-149, doi:10.1016/j.nbd.2004.11.011 (2005). [↩]Lundgren, J., Smith, M. L., Blennow, G. & Siesjo, B. K. Hyperthermia aggravates and hypothermia ameliorates epileptic brain damage. Experimental brain research. Experimentelle Hirnforschung. Experimentation cerebrale 99, 43-55 (1994). [↩]Laatikainen, T., Salminen, K., Kohvakka, A. & Pettersson, J. Response of plasma endorphins, prolactin and catecholamines in women to intense heat in a sauna. European journal of applied physiology and occupational physiology 57, 98-102 (1988). This study reinforces ref #15 in terms of the norepinephrine response but this demonstrates it in women. Also, the smaple size is small (N=11), so it good to have multiple studies showing similar effects. [↩]Salbaum, J. M. et al. Chlorotoxin-mediated disinhibition of noradrenergic locus coeruleus neurons using a conditional transgenic approach. Brain research 1016, 20-32, doi:10.1016/j.brainres.2004.03.078 (2004). [↩]Gregg, C. et al. White matter plasticity and enhanced remyelination in the maternal CNS. The Journal of neuroscience : the official journal of the Society for Neuroscience 27, 1812-1823, doi:10.1523/JNEUROSCI.4441-06.2007 (2007). [↩]Christman, J. V. & Gisolfi, C. V. Heat acclimation: role of norepinephrine in the anterior hypothalamus. J Appl Physiol (1985) 58, 1923-1928 (1985). [↩]Wigal, S. B. et al. Catecholamine response to exercise in children with attention deficit hyperactivity disorder. Pediatric research 53, 756-761, doi:10.1203/01.PDR.0000061750.71168.23 (2003). [↩]Goekint, M., Roelands, B., Heyman, E., Njemini, R. & Meeusen, R. Influence of citalopram and environmental temperature on exercise-induced changes in BDNF. Neuroscience letters 494, 150-154, doi:10.1016/j.neulet.2011.03.001 (2011). This study had an N=8 (okay, tiny) but… it demonstrated that hyperthermia and exercise synergize to elevate BDNF. This is awesome. Who doesn’t want more BDNF? [↩]van Praag, H., Christie, B. R., Sejnowski, T. J. & Gage, F. H. Running enhances neurogenesis, learning, and long-term potentiation in mice. Proceedings of the National Academy of Sciences of the United States of America 96, 13427-13431 (1999). [↩]Maniam, J. & Morris, M. J. Voluntary exercise and palatable high-fat diet both improve behavioural profile and stress responses in male rats exposed to early life stress: role of hippocampus. Psychoneuroendocrinology 35, 1553-1564, doi:10.1016/j.psyneuen.2010.05.012 (2010). [↩]Pedersen, B. K. Muscle as a Secretory Organ. Comprhensive Physiology (2013). [↩]Koltyn, K. F., Robins, H. I., Schmitt, C. L., Cohen, J. D. & Morgan, W. P. Changes in mood state following whole-body hyperthermia. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group 8, 305-307 (1992). [↩]Liu, X. L. et al. [Therapeutic effect of whole body hyperthermia combined with chemotherapy in patients with advanced cancer]. Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences 31, 350-352 (2006). [↩]Narita, M. et al. Heterologous mu-opioid receptor adaptation by repeated stimulation of kappa-opioid receptor: up-regulation of G-protein activation and antinociception. Journal of neurochemistry 85, 1171-1179 (2003). This study was done in mice but shows that repeated activation of kappa opioid receptor causes mu opioid receptor to become more sensitive to beta-endorphin. This study provides a mechanism by which the dysphoric feeling from exercise or heat stress can ultimately result in a better “endorphin high.” [↩]Xin, L., Geller, E. B. & Adler, M. W. Body temperature and analgesic effects of selective mu and kappa opioid receptor agonists microdialyzed into rat brain. The Journal of pharmacology and experimental therapeutics 281, 499-507 (1997). [↩]Heckmann, J. G., Rauch, C., Seidler, S., Dutsch, M. & Kasper, B. Sauna stroke syndrome. Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association 14, 138-139, doi:10.1016/j.jstrokecerebrovasdis.2005.01.006 (2005). This reference is only an N=1 where a a man had consumed several glasses of wine before he got in the sauna and was, subsequently, found dead. Alcohol consumption while in the sauna can cause severe dehydration, hypotension, arrhthymia, and embolic stroke. This is also reviewed in reference #1 [↩]

Either will be fine. You can lift heavy and do fewer reps or lift lighter and do more reps. Both will build similar amounts of muscle.Read this for more details:How Many Reps Should You do to Build Muscle?How many reps should you do to build muscle? Which rep ranges build the most muscle?These are deeply common questions that don’t seem to get answered too well. Meathead bros have oversimplified that moderate rep ranges around 8-12 reps are the holy grail for muscle growth. Their logic is that their favorite bodybuilder used this rep range, so it must be the best.I like to take a more objective approach to find the truth instead of listening to guys who probably injected a few needles up their rear end. To do this, I’m going to analyze the science behind rep ranges and find practical recommendations which you can apply to your training today.Now I totally understand if you don’t care about the science and just want to look swole. Just scroll to the bottom and read the recap, but if you happen to have some time, don’t skip ahead in this article. Learning the deeper science will give you a better understanding on how to train smarter.Anyways, let’s get into it.To find the most optimal rep ranges, here’s my plan of attack.Explain the obvious stuff.Explain the not so obvious stuff by dissecting the science.Consider all the pros and cons of each rep range.Give you the most favorable recommendations so you can train within a rep range that gets you looking jacked to the gills.To break this all down, I’ll be talking about rep ranges as low (1-6), moderate (6-15), and high (15+).Obviously the lower the rep range, the more weight you’d use and the higher the rep range, the less weight you would use, so assume the effort is relatively the same.The Obvious StuffThere are some obvious benefits to certain rep ranges. I’ll make this section short and sweet because these obvious benefits aren’t muscle growth and I know that’s what you really care about.The first obvious benefit is in the lower rep ranges. Training in the lower rep ranges is gets you stronger than higher rep ranges (1). This is pretty predictable as using heavier loads will get you better at lifting heavy things. Powerlifters often train in this rep range because they’re purely focused on getting stronger not necessarily bigger.The next obvious benefit is in the higher rep ranges. Training in the higher rep ranges is clearly better at improving muscular endurance (2). Again pretty obvious because if you lift a light load and do a ton of reps, you’re going to get really good muscular endurance from building up a hefty work capacity. This is why CrossFit athletes do very high rep sets. Their sport requires muscles to perform and endure long periods of performance.The Not So Obvious StuffHere’s where things get more complicated and extremely misunderstood. If low reps are better for strength and high reps are better for endurance, then moderate reps must be the hypertrophy rep range right?Well not quite. Research has not only shown all rep ranges can build muscle, but that all rep ranges end up building about the same amount (6,7,8,12).Long story short, the moderate rep range is not necessarily superior for muscle growth.This might be hard to grasp after hearing all the old school bodybuilders worship the 8-12 rep range, but once you understand how reps build muscle, you’ll see why all rep ranges can be viable muscle builders.The Scientific StuffYour muscles grow when sufficient mechanical tension is placed on them signaling for muscle growth to occur.For a rep to place sufficient mechanical tension and trigger optimal hypertrophy, here’s what it needs:a high level of motor unit recruitmentcombined with a naturally slow muscle fiber contraction velocity.If you’re a bit lost with the sciency terms, don’t worry. I’ll break it down simply.Let’s start with the first component which is a high level of motor unit recruitment.What Are Motor Units?A motor unit is basically a motor neuron that controls muscle fibers. To grow a muscle fiber, it must be activated by a motor unit.Low threshold motor units tend to control type 1 muscle fibers which don’t have much growth potential. Trying to get big by growing type 1 fibers is like trying to build a mansion using Legos. It’s just not effective.That’s where type 2 muscle fibers come in. These muscle fibers are bigger, badder, and have far more potential to grow (3). They are controlled by high threshold motor units, so one of the keys to triggering hypertrophy is recruiting as many high threshold motor units as possible.How Do You Do This?Motor units are recruited in order of size with the low or small motor units being recruited first, then high threshold motor units later depending on the effort needed (4).When you lift a light or moderate weight, small motor units are being first recruited to perform the task. As you start to fatigue and the low motor units produce less force, your body recruits higher threshold motor units towards the end of the set to compensate.On the other hand when more force is immediately required, your body will recruit more motor units sooner, so if you lift a really heavy weight like your 3-rep max, all motor units are recruited on the first rep in order to complete the high demanding task.Long story short, you can reach high levels of motor unit recruitment by lifting a heavy load or lifting a moderate/light load to or near failure.Recruiting Them is Not EnoughRemember recruiting the muscle fibers is only one part of the equation. The fibers have to experience sufficient tension from a slow contraction velocity.For low rep training, this is easy because your muscles contract slowly during heavy sets anyways, thanks to the weight being heavy.For higher rep training with moderate/light loads, to achieve a naturally slow muscle contraction, you must take the set near failure where your lifting speed naturally slows down.I emphasize the word naturally because you might not get optimal hypertrophy by deliberately slowing down your concentric lifting speed especially in the final reps. By deliberately slowing down, you are not applying as much force meaning you can’t achieve maximum motor unit recruitment.This means to reap optimal hyptertrophy with higher rep training, you have to lift with maximal intent and let fatigue gradually slow down.This allows for maximum force output and sufficient tension to be placed on the most recruited muscle fibers which causes the glorious process of our muscles getting noticeably bigger and our bodies looking hotter.All of this is why higher rep sets need to be taken near failure to trigger hypertrophy, but the tempo towards the final reps can’t be intentionally slowed down.Why All Rep Ranges Build MuscleSo here’s what you’ve learned so far. The reps that trigger significant hypertrophy are ones that reach high levels of motor unit recruitment and place sufficient tension on the muscles recruited by having a naturally slow contraction velocity (5).These reps are often called hypertrophic reps and is the reason why sets taken close to failure cause more muscle growth than sets that don’t. The closer you get to failure the more hypertrophic reps you achieve (9).This explains why studies show all rep ranges can build similar amounts of muscle when volume equal (6,7,8,12)With a low rep set like a set of 5, all 5 reps are hypertrophic reps because the load is difficult enough to trigger full motor unit recruitment from the start and promote a naturally slow contraction velocity thanks to the heavy weight.With a moderate rep set like a set of 10, the first 5 reps aren’t very hypertrophic because not enough motor units are recruited and fatigue hasn’t placed sufficient tension yet, but the last 5 reps are likely hypertrophic as fatigue forces more motor units to be recruited and a naturally slower contraction velocity occurs.The same thing with a high rep set like a set of 15. The first 10 reps are essentially setting you up for the last 5 to trigger substantial hypertrophy.The end result is the same in nearly every study. The totality of the stimulus (muscle building signal) from all rep ranges ends up being the same. This is why pretty much all rep ranges build muscle just fine.The First ExceptionHowever there are 2 exceptions.The first exception are very low reps done on their own. If you do only very low reps like sets of 1-4 reps, you have less opportunity to get as many hypertrophic reps to stimulate sufficient growth (10, 11).So low rep sets are still viable muscle builders, but not when they’re too low and done on their own.The Second ExceptionThe next exception are rep ranges that are excessively too high. We already know high rep ranges can build just as much muscle, but studies show going too high compromises hypertrophy.If the load is too light, even if you take the set all the way to failure, it still results in inferior gains. With loads below 30% of your 1-RM, higher threshold motor units simply don’t get recruited which as I mentioned earlier is one of the key components to maximum muscle growth (13,14).This is one of the many reasons exercise classes suck at building muscle. They tend to use excessively light loads. You could do a billion reps with those tiny pink dumbbells, but the hypertrophy would be minimal.However, as long as you’re using at least 40% of your 1-rep max, your hypertrophy won’t be compromised (14). A good rule of thumb is to never use a load that allows you to train past 40 reps.If you’re able to lift something over 40 times to failure, it’s likely too light and compromising progress.Science Meets PracticeNow outside of the 2 exceptions I mentioned, optimal muscle growth can be achieved in pretty much any reasonable rep range.There’s no reason to limit yourself to only doing 8-12 reps. Maximum growth can be accomplished from anywhere between 5 and 30 reps as long as load is chosen appropriately and sets are taken near failure if you’re training with a moderate/high rep range.That being said, if main goal is muscle growth, I do recommend training in a variety of rep ranges with an emphasis on moderate rep ranges between 6-15.Here’s why:Low rep ranges are more stressful for joints and connective tissues.Low rep ranges require longer warm ups as the load is higher.Low rep ranges require longer rest times between sets.High rep ranges take longer per set, but achieve the same level of hypertrophy as moderate rep ranges.High rep ranges might be stopped short if your cardiovascular endurance sucks.High rep ranges make you look less impressive because you’re forced to use lighter weights. Not good when your gym crush is staring at you.So practically speaking, the most bang for your buck is training around 6-15 reps, but incorporating some low/high rep training is also great for boosting strength/endurance without sacrificing any muscle growth.Hope this helps you get epically jacked my friend. Until next time.ReferencesSchoenfeld, Brad J, et al. “Effects of Different Volume-Equated Resistance Training Loading Strategies on Muscular Adaptations in Well-Trained Men.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, Oct. 2014, Effects of different volume-equated resistance training loading strategies on muscular adaptations in well-trained men..Schoenfeld, Brad J, et al. “A Comparison of Increases in Volume Load Over 8 Weeks of Low-Versus High-Load Resistance Training.” Asian Journal of Sports Medicine, Kowsar, 16 Jan. 2016, A Comparison of Increases in Volume Load Over 8 Weeks of Low-Versus High-Load Resistance Training.Pope, Zachary K, et al. “Action Potential Amplitude as a Noninvasive Indicator of Motor Unit-Specific Hypertrophy.” Journal of Neurophysiology, American Physiological Society, 1 May 2016, Action potential amplitude as a noninvasive indicator of motor unit-specific hypertrophy..“Skeletal Muscle Mechanics.” ScienceDirect, Academic Press, 24 Feb. 2017, Skeletal Muscle Mechanics.Piazzesi, Gabriella, et al. “Skeletal Muscle Performance Determined by Modulation of Number of Myosin Motors Rather than Motor Force or Stroke Size.” Cell, U.S. National Library of Medicine, 16 Nov. 2007, Skeletal muscle performance determined by modulation of number of myosin motors rather than motor force or stroke size..Schoenfeld, Brad J, et al. “Muscular Adaptations in Low- versus High-Load Resistance Training: A Meta-Analysis.” European Journal of Sport Science, U.S. National Library of Medicine, 2016, Muscular adaptations in low- versus high-load resistance training: A meta-analysis..Scientific Research Publishing. “Low-Load Bench Press Training to Fatigue Results in Muscle Hypertrophy Similar to High-Load Bench Press Training.” International Journal of Clinical Medicine, Scientific Research Publishing, 26 Feb. 2013, Low-Load Bench Press Training to Fatigue Results in Muscle Hypertrophy Similar to High-Load Bench Press Training.Mitchell, Cameron J, et al. “Resistance Exercise Load Does Not Determine Training-Mediated Hypertrophic Gains in Young Men.” Journal of Applied Physiology (Bethesda, Md. : 1985), American Physiological Society, 1 July 2012, Resistance exercise load does not determine training-mediated hypertrophic gains in young men.Goto, Kazushige, et al. “The Impact of Metabolic Stress on Hormonal Responses and Muscular Adaptations.” Medicine and Science in Sports and Exercise, U.S. National Library of Medicine, June 2005, The impact of metabolic stress on hormonal responses and muscular adaptations..Schoenfeld, Brad J, et al. “Differential Effects of Heavy Versus Moderate Loads on Measures of Strength and Hypertrophy in Resistance-Trained Men.” Journal of Sports Science & Medicine, Uludag University, 1 Dec. 2016, Differential Effects of Heavy Versus Moderate Loads on Measures of Strength and Hypertrophy in Resistance-Trained Men..Dankel, Scott J, et al. “Muscle Adaptations Following 21 Consecutive Days of Strength Test Familiarization Compared with Traditional Training.” Muscle & Nerve, U.S. National Library of Medicine, Aug. 2017, Muscle adaptations following 21 consecutive days of strength test familiarization compared with traditional training..Schoenfeld, Brad J, et al. “Strength and Hypertrophy Adaptations Between Low- vs. High-Load Resistance Training: A Systematic Review and Meta-Analysis.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, Dec. 2017, Strength and Hypertrophy Adaptations Between Low- vs. High-Load Resistance Training: A Systematic Review and Meta-analysis..Schoenfeld, Brad J, et al. “Muscle Activation during Low- versus High-Load Resistance Training in Well-Trained Men.” European Journal of Applied Physiology, U.S. National Library of Medicine, Dec. 2014, Muscle activation during low- versus high-load resistance training in well-trained men..Lasevicius, Thiago, et al. “Effects of Different Intensities of Resistance Training with Equated Volume Load on Muscle Strength and Hypertrophy.” European Journal of Sport Science, U.S. National Library of Medicine, July 2018, Effects of different intensities of resistance training with equated volume load on muscle strength and hypertrophy..