Squats do increase testosterone, but the boost is temporary. Heavy squats can raise testosterone levels immediately after a workout, with levels returning to baseline within about an hour. More importantly, this short-lived spike doesn’t appear to drive muscle growth the way many people assume.
The Acute Spike Is Real but Brief
When you perform heavy squats, your body responds with a measurable increase in circulating testosterone. Research on resistance exercise protocols shows testosterone concentrations rise by roughly 3.8 nmol/L immediately after completing sets to failure. That bump is statistically significant, but it doesn’t last. Within one hour of finishing the workout, testosterone drops back to pre-exercise levels with no meaningful difference from baseline.
This pattern holds regardless of whether you’re training upper or lower body. But because squats recruit such a large amount of muscle tissue (glutes, quads, hamstrings, core), they tend to produce a stronger hormonal response than exercises targeting smaller muscle groups. The National Strength and Conditioning Association notes that the hormonal response to exercise correlates directly with metabolic stress: the more muscle mass involved, the greater the release of anabolic hormones. That’s why compound movements like squats, deadlifts, and power cleans sit at the top of the list.
Free-Weight Squats Outperform Machines
If maximizing the hormonal response matters to you, free-weight barbell squats produce a larger testosterone increase than machine-based alternatives. In a study comparing squats to leg presses performed at the same intensity (6 sets of 10 reps), both exercises raised testosterone immediately after training. But the free-weight squats produced significantly higher increases at the immediate post-exercise measurement. The likely explanation is that barbell squats demand more stabilizer muscle activation and overall neuromuscular effort, creating greater metabolic stress.
Volume and Intensity That Maximize the Response
Not all squat workouts produce the same hormonal response. A study of 28 experienced powerlifters tested three different volumes of barbell squats at 90% of their one-rep max: 3 sets, 6 sets, and 12 sets, all with three reps per set. Six sets emerged as the sweet spot. Both 6 and 12 sets produced significant post-exercise increases in growth hormone, but the researchers concluded that six sets of high-intensity squats was the optimal volume for triggering a meaningful endocrine response without excessive fatigue.
The general recipe for the strongest hormonal response combines heavy loads, moderate-to-high volume, large muscle groups, and relatively short rest periods (60 to 90 seconds between sets). Protocols with lower intensity, small muscle involvement, or long rest periods between sets are less effective at stimulating hormonal changes.
Squats Don’t Raise Your Resting Testosterone
Here’s where the popular narrative breaks down. While individual squat sessions produce a temporary spike, months or years of consistent squatting do not raise your baseline testosterone level. A systematic review and meta-analysis pooling data from multiple resistance training studies found that long-term training had essentially zero effect on resting testosterone. The overall effect size was -0.003, which is statistically indistinguishable from nothing.
This was particularly clear in older men, where the belief that lifting heavy can restore declining testosterone proved unfounded. The practical takeaway from that research: resistance exercise is not a reliable strategy for increasing your baseline hormonal levels. Interestingly, the same review suggested that aerobic and interval training may have a modest edge over resistance training when it comes to influencing resting testosterone, though the evidence remains limited.
The Spike Probably Doesn’t Build Extra Muscle
This is the part most fitness content leaves out. The acute testosterone spike from squats, while real, does not appear to play a meaningful role in muscle growth. Multiple lines of evidence now challenge the long-held “hormonal hypothesis” that post-exercise hormone surges drive hypertrophy.
A study of 56 young men measured acute post-exercise testosterone, growth hormone, and IGF-1 at the midpoint of a 12-week resistance training program. None of these hormonal elevations correlated with gains in lean body mass or leg press strength. The spikes were real, but they predicted nothing about who actually built muscle.
Perhaps the most striking evidence comes from sex-based comparisons. Despite men experiencing a 45-fold greater testosterone exposure than women in the first hour after heavy resistance exercise, the rate of muscle protein synthesis was nearly identical between sexes. Women showed a 2.7-fold increase above resting rates, while men showed a 2.3-fold increase. If acute testosterone spikes were driving muscle repair and growth, men should have shown dramatically higher protein synthesis. They didn’t.
The scientific consensus, summarized in a review published in Exercise and Sport Sciences Reviews, is direct: acute post-exercise rises in testosterone, growth hormone, and IGF-1 are “neither sufficient nor necessary” for stimulating muscle protein synthesis or maximizing hypertrophy. Muscles grow because of the mechanical tension and damage from the exercise itself, not because of a brief hormonal wave afterward.
What This Means for Your Training
Squats remain one of the most effective exercises you can do. They build strength, increase muscle mass, improve bone density, and develop functional movement patterns. Those benefits are well established and not in question. What the research challenges is the specific idea that squats are valuable because they “boost testosterone.” The boost exists, but it’s fleeting, it doesn’t raise your baseline levels, and it doesn’t appear to be the mechanism behind muscle growth.
If you’re choosing squats over other exercises primarily for the hormonal effect, you can relax that concern. Choose squats because they load the largest muscles in your body through a full range of motion, because they build real-world strength, and because progressive overload on compound lifts is the most reliable path to getting stronger. The testosterone spike is a side effect of hard training, not the reason hard training works.