Testosterone Increases with Large Muscle Mass Exercises

Testosterone levels are also influenced by the amount of muscle mass activated in response to exercise.  Olympic lifts, jump squats, and deadlifts all produce large increases in testosterone^31,32.  Although most people would rather perform a bench press than jump under a squat bar, the bench press is not going to increase testosterone production like a squat.  For example researchers investigated the effects of 5 sets of 10 repetitions of bench press versus 5 sets of 10 repetition jump squats, with 2 minutes rest between sets in 12 resistance trained men. Testosterone was raised higher following the jump squat (15 %) then the bench press (7%). This suggests that exercises which recruit the most substantial amounts of muscle tissue will cause the greatest increases in testosterone³². It also reinforces the order of exercise principles. Generally exercises that recruit large muscle groups (squats, deadlifts, chin-ups) should be performed before isolation exercises (leg extensions, leg curls, ect). As testosterone is concerned, the larger exercise may raise testosterone levels and exert its effects on the smaller isolation type exercises.   It has been suggested that large muscle mass exercises be performed prior to small muscle-mass exercises. The performance of large muscle-mass exercises (i.e. squat,  deadlift, power clean) early in the workout produce elevations in testosterone, which  potentially may expose smaller muscles to a greater response than that resulting from performance of small muscle mass exercises only. For example, one study measured muscle strength changes in the bicep strength following 9 weeks of resistance training. However, one group performed a workout consisting of bicep curls only and a second group performed squats prior to bicep curls. Performing bicep curls exercises only failed to acutely elevate testosterone significantly. However, testosterone was significantly elevated when squats were performed first, and muscle strength increased to a greater extent as well when both lower- and upper-body exercises were performed³³. These data provide support for performing large muscle mass, multiple-joint exercises early in a workout and smaller muscle mass exercises later in the workout when training to enhance muscle strength.

World renowned Russian strength coach Pavel Tsatsouline wrote in his book, that if he had to choose one exercise to perform it would not be the squat, but the barbell deadlift.  The deadlift recruits not only the legs, but the arms, abs, and lower back as well.    It has been reported that significant increases in testosterone occur after deadlights in college age men; however, maximal and submaximal efforts in the bench press resulted in smaller increases in testosterone⁷ you can still perform isolation exercises such as bicep concentration curls, just perform these exercise after the larger exercise.  For example, if an athlete performs squats before biceps curls, the biceps may be exposed to higher levels of circulating testosterone. Dynamic power schemes, often employed to maximize explosive power have also produced significant androgen responses. Dynamic power schemes, often employed to maximize explosive power and functional performance, have also produced significant androgen responses. For example, total (18%) and free TST (30%) increased in response to half-squat lifts performed with a load of 50% 1RM²⁹. If you are looking to put on size and strength walk right past that leg extension to the squat rack.  Testosterone levels did not increase from pre to post exercise for younger and older men to upper and lower body isolation-type (leg extension) resistance exercise on a Nautilus machine consisting of 3 sets of 10-repetitions⁴.   Contrary to these finding, significant increases in testosterone responses of older and younger men in response to a high intensity large muscle mass squat (large muscle mass) protocol⁵. 

What are the Stimulators of Testosterone?

So here is the million dollar question researchers are asking: What is the mechanism or how does intense exercise stimulate testosterone production?  Testosterone levels under resting conditions are influenced by a hormone called leutinizing hormone (LH), which stimulates Leydig cells (cells located in the testes) to secrete testosterone, however during brief intense resistance exercise testosterone levels have been reported to increase despite no increases in LH¹⁰.   This suggests that testosterone is not being increased thru normal physiological stimulation but other means such as changes in blood volume which result in a super concentration of blood particles.

Decreased Plasma Volume during  Exercise Increases Testosterone

A proposed mechanism for increased testosterone levels during exercise is what is called a plasma volume shifts, which concludes that during high intensity resistance exercise as you muscles become pumped with blood, water or plasma is displaced from your circulatory system, as a result your blood becomes more concentrated with active metabolites (in this case testosterone).  For example, testosterone levels have been found to increase after sitting in a sauna²⁵.   Testosterone levels are not actually increasing, changes in blood volume due to sweat loss result in a supersaturation of testosterone levels in the circulatory system.  Kraemer et al. reported that after a resistance training protocol of three sets of bench press, lat-pulldowns, leg extension, and leg curls performed at a 10-RM load for 10 repetitions or until muscular failure resulted in a significant increase in testosterone levels, but when he corrected for the plasma volume shifts or the amount of fluid lost from blood and found that there was no change in testosterone¹². However, even if there are no actual increases in testosterone that occurs with resistance exercise the elevated levels in the blood have more availability to bind with androgen receptors in muscles producing a superior anabolic response.

Can Lactic Acid Stimulate Testosterone?

The absent response of LH to an acute bout of resistance exercise despite an increase in testosterone has led researchers to speculate other mediators are influencing testosterone production.  Possible mechanisms for increasing testosterone levels during high intensity exercise are due to increased circulating lactic acid levels that are being produced from high intensity training.  Lactic acid has been shown to stimulate testosterone release in vitro (i.e. which means in the test tube)¹¹.    Researchers exposed the testosterone producing portion of the cell (i.e. Leydig cells) to lactic acid and found that administration of lactic acid dose-dependently increased the basal testosterone production. 

Testosterone Stimulation thru Adrenaline?

Catecholamines or adrenaline is a possible stimulator of testosterone in men as well.  It has been reported that men competing in competition and win have increased testosterone production which is also takes place with large increases in adrenaline which may be stimulating testosterone secretion ^{13, 14}.  Robert Sapolsky a world renowned endocrinologist who studies male apes reports that when male apes fight other apes for females, the winning ape has large increases in testosterone while the losing ape has lowered testosterone.   He reports that in ape's testosterone could be increased by other mechanism than the LH pathways which may be true in humans as well¹⁵.  He suggested that sympathetic stress enhances the secretion of adrenaline, which has a stimulatory effect on testosterone within minutes, whereas cortisol released from the adrenals also inhibits testosterone production from the testes just as quickly.  Thus he suspects the adrenaline rush of winning increases testosterone while losing increases cortisol which decreases testosterone.  Researchers put the adrenaline and testosterone theory to the test in young males.  The heavy weight lifting consisted of four sets of six squats at 90-95% of a six-repetition maximum (RM), while the moderate weight lifting consisted of four sets of 9 or 10 repetitions at 60-65% of a 1-RM.  The weight and number of repetitions were manipulated such that the total weight lifted for the two sessions were equal. Schwab hypothesized because the exercise bout was brief, possibly epinephrine and norepinephrine, which have been shown to increase during exercise to the magnitude of the intensity of the exercise, could have significantly increased testosterone levels in response to the exercise bout¹⁶.