Get the best hormone response from exercise by performing sprint intervals and heavy strength training. Exercise causes physiological stress, and two common pitfalls of training are putting too much or too little stress on the body because lead to a catabolic, muscle degrading environment. Intense sprint intervals will trigger a cortisol stress hormone response, but if you program your sprints the right way, you can trigger a greater testosterone response and shift the body into an anabolic state. To maximally manipulate the stress response and manage cortisol, do both sprints and a high volume of heavy strength training.
A new study in the British Journal of Sports Medicine compared the hormone response of two sprint interval protocols and a circuit training program. The study measured testosterone and cortisol in trained young men and had them perform the following three exercise trials: a 30-minute tempo run at lactate threshold, 30-minutes of intense intervals (3 minutes at 90 percent of maximal with 2 minute recovery), and 30-minutes of circuit weight training in which participants lifted for 30 seconds and then had a 30 second recovery.
Only the intervals triggered a significant testosterone response, indicating that a high-intensity is necessary to produce an anabolic environment. The tempo run and the circuit training did raise testosterone above resting levels, but not to a point that was statistically significant. Rating of perceived exertion was also measured and was highest following the intervals as well, indicating that the most challenging mode elicited the greatest anabolic response. RPE was 16 out of 20 for the intervals, compared to the tempo run that was 15, and circuit training that was 13, pointing to an association between level of difficulty and testosterone response. Heart rate was also associated with a favorable anabolic response, indicating that monitoring peak heart rate when training could be a strategy for monitoring testosterone production.
Cortisol was highest after the intervals, but because of the greater testosterone response, the ratio between the two was more favorable for muscle and tissue building. The tempo run also triggered cortisol, but because the testosterone response was minimal, the ratio was less favorable. The circuit training program resulted in a minimal cortisol and testosterone response, indicating that it was not strenuous enough to be effective for tissue remodeling. Researchers did not include the weights used for the circuit training program in the research report, but it is likely the weights lifted were not very heavy because a 30-seconds on, 30-seconds off program can be extremely challenging if performed at a heavy weight and high speed.
Previous evidence supports the researchers’ conclusion that a high level of intensity is necessary to raise testosterone from sprinting and resistance training. For example, research shows that heavy lifts with a high volume will trigger the most testosterone and the good news is that data show that performing a weight training program is an ideal way to offset the bump in cortisol that comes with sprinting.
One study of rugby players from New Zealand found that a training protocol that includes 4 exercises for 3 sets of 4 reps at 85 percent of the one RM results in the most favorable anabolic response, producing a 38 percent decrease in cortisol from resting levels. In fact, the study compared the 85 percent protocol with three others that were matched for volume (performed at 70 percent of the 1RM, 55 percent of the 1RM, and 40 percent of the 1RM), and all four resulted in a drop in cortisol following training.Maximize tissue and muscle building by ensuring you are doing the following four things:
1) Perform strength training with a high volume of heavy lifts. Use large muscle groups and multi-joint exercises such as Olympic lifts, squats, deadlifts, and chest press.
2) Perform sprint intervals at a high intensity—but don’t overdo it and send yourself into a catabolic state.
3) Shoot for a heart rate in the 85 to 90 percent of max range for the greatest testosterone response from sprint intervals.
4) Avoid going too easy—this won’t boost testosterone but will produce cortisol, causing a tissue degrading state.
References: Tanner, A., Nielsen, B., et al. Salivary Steroid Hormone Response in Trained Men to Running and Circuit Training Sessions. British Journal of Sports Medicine. December 2011. 45(15), A6.