Nobody talks about muscle loss the way they talk about heart disease or diabetes. But sarcopenia — the progressive loss of muscle mass with age — is one of the most significant predictors of early death, hospitalisation, and loss of independence in men over 50. And it starts in your 40s.
From around age 40, the average man loses 1-2% of his muscle mass per year without deliberate intervention. By 70, that can mean losing 30% of the muscle you had in your prime. The consequences are not just aesthetic.
WHAT MUSCLE ACTUALLY DOES FOR YOU
- Metabolic regulation: Muscle is the primary site of glucose disposal in the body. More muscle means better insulin sensitivity and lower blood sugar — independent of body fat.
- Hormonal health: Resistance training raises testosterone and growth hormone. Muscle loss accelerates the decline of both.
- Bone density: Muscle pulls on bone during contraction. Without that mechanical stress, bone density falls — raising fracture risk.
- Cardiovascular protection: Grip strength — a proxy for overall muscle mass — is one of the strongest predictors of cardiovascular mortality in middle-aged men.
- Mental health: Resistance training has comparable effects to antidepressants in multiple clinical trials for mild to moderate depression.
"Muscle mass is not a vanity metric. It is a survival metric."
THE TWO INPUTS THAT MATTER
Building and preserving muscle after 40 requires two things above all else: adequate protein and progressive resistance training. Everything else is secondary.
On protein: most men over 40 eat around 70-80g of protein per day. The research on muscle preservation suggests you need 1.6-2.2g per kilogram of bodyweight. For an 85kg man, that's 136-187g per day. The gap between what most men eat and what they need is enormous.
On training: you don't need to be in the gym five days a week. Two to three sessions of compound resistance training per week — squats, deadlifts, rows, presses — is enough to preserve and build muscle at any age. The key word is progressive. You need to be lifting slightly more, or doing slightly more reps, over time. Maintenance is not enough.
Start now, not later
The best time to start building muscle was ten years ago. The second best time is today. The men I work with who are in their 50s and 60s and still lean, strong, and energetic all have one thing in common: they started taking muscle seriously before they felt they needed to.