Why the Male Formula Runs Higher
BMR (men)
The male version of Mifflin-St Jeor adds 5 instead of subtracting 161, a roughly 166-point adjustment reflecting that men, on average, carry a higher percentage of lean muscle mass and lower body fat percentage than women at the same height and weight. Since muscle is more metabolically active than fat tissue, this translates into a higher typical BMR.
The Role of Testosterone
Testosterone supports muscle mass, which supports BMR. Testosterone plays a direct role in building and maintaining lean muscle tissue. This is one of the underlying biological reasons men tend toward higher average muscle mass and, by extension, higher BMR — not because testosterone directly raises metabolic rate on its own, but because of its effect on body composition over time.
Typical BMR Ranges by Age (Average Build)
| Age Range | Typical BMR Trend |
|---|---|
| 20s–30s | Near-peak, highest typical range |
| 40s–50s | Gradual decline, often tied to reduced muscle mass and activity |
| 60s+ | Noticeably lower without active resistance training |
Exact numbers vary considerably with individual height, weight and activity — use the calculator above for your personal figure rather than relying on averages.
What Actually Moves a Man’s BMR
1 Resistance training
Building and maintaining muscle mass is the single most effective controllable lever, particularly as natural testosterone and activity levels tend to decline gradually with age.
2 Avoiding excessive, repeated cutting
Aggressive, repeated calorie deficits without adequate protein or resistance training accelerate muscle loss, working directly against BMR.
3 Sleep and stress management
Poor sleep and chronic stress affect hormone levels, including testosterone, which over time can influence body composition and resting energy expenditure.
Frequently Asked Questions
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