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What Time Of Day Is Best For Your Workout?

Harnessing Your Circadian Rhythms to
Derive the Most Benefit From Your Workouts

In the world of day-to-day training, there are two types of people. There’s the person who arrives at the gym bright and early, before work, looking to get their metabolism churning and jump start their day with a high-intensity workout. This person might be fueled with just a cup of coffee and looking to turn an early-hour caloric deficit into some excess fat loss. If this person is male, they also might be looking to harness a morning peak in testosterone levels for added strength and aggression.

And then there’s your afternoon/early evening workout warrior. This person knows that coordination, reaction time, and cardiovascular efficiency are typically at their peak during these later hours, and each is essential to maximum performance. Contrary to the beliefs of our early bird, physical strength maxes out at this juncture of the day as well. And finally, heading out to the gym is certainly preferable to heading home for some TV time or out with the after-work happy hour crowd.

Which philosophy makes better sense from the standpoint of training success? Or is there some other time? Should you be training at lunch time? How about joining a 24-hour gym and showing up at 3am? Is there a magic hour for maximum performance, muscle mass increase, and fat loss? We’ve taken a look at the most recent science and we believe we have a definitive answer.

Your Body’s Daily Metabolic and Hormonal
Cycles are as Punctual as Clockwork

Most people think of circadian rhythms in terms of the sleep cycle, but in reality, there’s plenty more to it than the transition between rest and wakefulness. Your lowest body temperature occurs at 4:30am for instance, and highest occurs at about 5pm. Your deepest sleep cycle occurs at 2am and your period of highest alertness manifests around 10am. Throughout the day we also experience hormonal fluctuations, especially with two of great interest with regard to training: cortisol and testosterone.

Upon waking, and throughout the morning, the blood carries a high concentration of testosterone. Due to testosterone’s role in protein synthesis, not to mention strength, vitality and overall wellness, it seems logical to suggest that morning resistance training elicits superior hypertrophy and strength gains. But as testosterone is elevated in the morning so is cortisol, potentially limiting testosterone’s hypertrophic affect. The high T levels also do not guarantee a strong hormonal response to training.

Later in the day, however, when the levels of each hormone have declined, the response of each is much stronger when provided a training stimulus (a strong cortisol response is also important for eliciting adaptation). It appears counterintuitive, but it’s true. The gains you’re looking for come from a strong hormonal response, and that response doesn’t peak in the morning.

Body Temperature and Movement
As a Foundation for Optimized Performance

Hormones are a fuel that nourishes our strength and muscle mass increase, but they aren’t the only catalyzing agent that you need to facilitate training. Enzymatic activity, nerve conduction velocity, muscular blood flow and joint limberness all affect performance, too. Though many athletes take the “tough it out and make gains” approach to training, using peak performance time to your advantage accelerates strength and mass gains. If you can perform better, you’ll train harder, potentially eliciting a greater physiologic response that boosts strength and mass gains.  

As we move and eat throughout the day, even if we are predominantly sedentary, body heat increases—boosting energy-producing enzymes, improving nerve conduction velocity and muscular blood flow while cultivating joint limberness. These are the factors behind afternoon peaks for coordination, reaction time, and strength.

We would be remiss if we didn’t also mention that there is a self reinforcing relationship between exercise and testosterone levels. Heavy compound moves (squats, deadlifts and bench presses especially) facilitate increases in blood-serum testosterone levels. An article published in the Journal of Strength and Conditioning Research illustrates that high load volume is the best training stimulus for increasing free testosterone. The researchers reported that completing 10 reps at 75% 1RM, with 2 minutes rest between sets, resulted in the greatest workout volume and highest testosterone levels. So working out optimizes the hormonal response essential for deriving maximum benefit from your workout.

Okay, So What is the Optimal Training Time?

By now you can see where we’re going with this. The best time to train—and derive maximum physique benefit from that training—is in the late afternoon to evening. At this point, the nervous system, endocrine system and musculoskeletal system are primed to work. It’s also when your body answers best with a strong hormonal response.

Later workouts time up well with life’s diurnal rhythm—leave work, hit the gym and train like you’ll never see weights again. Testosterone and cortisol respond accordingly so you adapt properly to your training, and a big post-training meal (i.e. dinner) promotes parasympathetic function, allowing you to rest and digest before bed. And sleep, of course, is ideally conducive to repair and recovery.

Hormonal Support: The Supplementation Advantage
Just because you’ve got your timing squared away doesn’t mean you should rest on your laurels. There’s still plenty you can do to tilt your hormonal odds even more into your favor. Take sleep, for instance. As you’re tucking yourself into bed after all your hard work, consider taking a superior-quality ZMA supplement. ZMA (a combination of zinc, magnesium and Vitamin B6) has long been associated with deeper, more restful sleep. Even better, both zinc and magnesium have been shown to significantly decrease levels of the catabolic hormone cortisol. (Cortisol, as we've said, is a trigger for hormonal response to training BEFORE your workout, but afterwards it's mostly associated with muscle-wasting catabolic activity in the cell.) A study conducted by researchers at Justus Liebig University in Germany revealed that triathlon athletes taking a magnesium supplement for 4 weeks had significantly lower cortisol at rest and after a marathon, compared to athletes taking a placebo. Keeping cortisol levels low can be critical for muscle and strength gains, as cortisol competes with testosterone, decreasing anabolism and enhancing muscle breakdown post-workout.

The most well-known research on ZMA's anabolic benefits is a study performed at Western Washington University in which researchers had NCAA football players take ZMA or a placebo nightly during an eight-week spring-training program. They discovered that the athletes taking the ZMA supplement experienced a greater than 30% increase in both free and total testosterone levels, and about a 4% increase in insulin-like growth factor 1 (IGF-1) levels, while those taking placebo had a 10% decrease in both free and total testosterone levels and a 22% decrease in IGF-1 levels. In addition to improvements in anabolic hormone levels and sleep quality, the ZMA athletes made significantly greater gains in strength and power compared to the placebo group.

The ZMA used in the study cited above was sourced directly from the industry leader in research and development of ZMA, Scientific Nutrition for Advanced Conditioning, or SNAC Systems. Unlike inferior ZMA formulas which can be sourced from inferior ingredients, ProSource brand ZMA is 100% SNAC sourced for peerless quality. It also functions as an ideal synergistic companion to other male hormonal support technologies, which brings us to one of the most transformational supplements in recent sports science history.

The Workout Warrior’s Edge: Natural Testosterone Support

If you’re training at your body’s optimal time, and want to kick things even further into overdrive, you should also consider supplementing with a high-quality natural testosterone-boosting product that will help you support free, unbound, and total testosterone levels. For this purpose, far and away the best option for you is the only true clinical-grade natural testosterone booster, AndroTest from ProSource.

AndroTest Clinical StudyAndroTest contains a full-spectrum protodioscin-rich botanical super-compound subjected to an ultra-advanced extraction and refinement process that yields an active ingredient standardized for a minimum of 40% bioactive protodioscin levels. An independent laboratory validated the effectiveness of AndroTest in a brand-specific clinical study that remains the gold standard for this category. Subjects in this independent clinical trial were aged 35 to 55 years and were randomized to take either AndroTest or a placebo for 4 weeks. Results indicated significant increases in free testosterone levels, up to 218% over baseline, and significant increases in total testosterone levels, as high as 275% over baseline. These are extraordinary results that go beyond those seen with some of the most potent synthetics tested in separate studies.

Further evidence for the hormonal-support efficacy of highly refined protodioscin continues to appear. A study published in 2013 illustrated that when stressed subjects took an active natural compound that is also found in AndroTest for 4 weeks, they had a 37% increase in testosterone status and 16% decrease in cortisol. In a report published in Andrologia in 2016, 65 men (aged 18-65) with no hormonal issues took an herbal extract containing 112 mg of protodioscin daily for 12 weeks. Body fat percentage, lean muscle mass gain, and hormone levels were analyzed during the period of treatment. It was concluded that taking the protodioscin-rich extract led to an increase in blood dihydrotestosterone levels, which coincided with decreased body fat percentage, and increases in lean mass. Along similar lines, in a pilot study published in the Journal of Sex and Marital Therapy (2016), 30 male patients with clinical androgen deficiency were given 750 mg of a protodioscin-rich extract daily for 3 months. The research team found that this supplementation produced a 33% increase in total testosterone and 6% increase in free testosterone in this cohort.   

It cannot be emphasized enough that the quality and efficacy of commercially available T-boosters varies widely. Many of these products are merely raw herbal extracts in a bottle and virtually none of these products have any real clinical validation to back them up. No other existing product rivals AndroTest for purity, potency, and efficacy. If you're over 25 years of age, adding AndroTest to your supplementation regimen is one of the best things you can do to support T levels and experience consequent improvements in vitality and response to training.


It should be noted that not everyone’s circadian rhythms are identical. There will always be variations in metabolic, cardiovascular, and hormonal cycles. (To cite an extreme example, a person who works nights will manifest entirely different physiological ebbs and peaks.) For most of us, though, finding our optimal training time requires just a little bit of experimentation.

Over the next few weeks train at different times within the late afternoon to evening window, and change the time in half-hour to hour increments. Take detailed notes on how you perform and recover. By the end of the experiment you’ll find your training-time sweet spot. And your training will be a lot more productive when your timing is right.

Read more about ProSource brand ZMA here.

Read more about AndroTest here.

Scientific References

Crewther B, Cronin J, Keogh J, Cook C. The salivary testosterone and cortisol response to three loading schemes. J Strength Cond Res. 2008 Jan;22(1):250-5.

Kilic M et al. The effect of exhaustion exercise on thyroid hormones and testosterone levels of elite athletes receiving oral zinc. Neuro Endocrinol Lett. 2006 Apr 25;27(1-2):247-252.

Lukaski HC. Magnesium, zinc, and chromium nutriture and physical activity. Am J Clin Nutr. 2000 Aug;72(2 Suppl):585S-93S.

Brillia, LR., Conte, V. Effects of a novel zinc-magnesium formulation on hormones and strength. J Exerc Physiol Online. 200; 3: 26-36.

Cardarelli R, Singh M, Meyer J, Balyakina E, Perez O, King M. The Association of Free Testosterone Levels in Men and Lifestyle Factors and Chronic Disease Status: A North Texas Healthy Heart Study. J Prim Care Community Health. 2014 Jan 26;5(3):173-179.

Salgado RM, Marques-Silva MH, Gonçalves E, Mathias AC, Aguiar JG, Wolff P. Effect of oral administration of Tribulus terrestris extract on semen quality and body fat index of infertile men. Andrologia. 2016 Jul 12. doi: 10.1111/and.12655. [Epub ahead of print]

Use as directed. Read all product label instructions and warnings thoroughly before use. A 4-week study of healthy males showed a 59.75% average increase in free testosterone compared to baseline and 59.88% average increase in total testosterone compared to baseline. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.