After 40, the body gradually begins to lose muscle mass — a process known as sarcopenia — at a rate of approximately 3–8% per decade, with the decline accelerating after 60.
Although these changes are part of ageing, they are not beyond influence. Strategic strength training and intentional joint care can significantly slow this decline, supporting metabolic health, protecting mobility and preserving independence.
Muscle Is More Than Strength
As we age, muscle is often viewed through a cosmetic lens — something that shapes how we look. But muscle plays a far more significant role in our health and longevity.
Muscle is metabolically active tissue. It helps clear excess glucose from the bloodstream and turn it into usable energy. The more muscle you have, the more efficiently your body manages blood sugar — supporting sustained energy levels and helping to reduce chronic inflammation.
Muscle also acts as an endocrine organ, releasing signalling molecules that influence bone strength, metabolic health and even brain function. In this sense, muscle is not cosmetic — it is protective.
Beyond metabolism, strength training improves balance and coordination — key factors in reducing the risk of falls, which remain a major cause of injury in older adults.
Why the Scale Doesn’t Tell the Full Story
Many people judge progress purely by the number on the scale. However, weight alone does not reflect what the body is truly made of.
Studies suggest that up to 20–50% of weight lost during calorie restriction can come from muscle tissue. This is especially important in the era of GLP-1 medications: while these treatments can drive substantial weight loss, muscle preservation still requires resistance training and adequate protein. Without it, metabolic resilience may suffer.
It is not only how much muscle we have, but the quality of that muscle that influences strength and resilience. With prolonged inactivity, muscle tissue can gradually become infiltrated with fat, reducing strength and function — even if overall body weight remains stable.
This is why body composition matters more than the number on the scale. Protecting muscle while reducing excess fat should be the true goal.
It Is Never Too Late
A common misconception is that muscle loss is an inevitable part of ageing that cannot be changed.
Encouragingly, studies show that significant muscle growth and strength improvements can still be achieved in people in their 80s and 90s, reinforcing that it is never too late to begin.
Strength training also applies mechanical loading to bones, which is crucial for maintaining bone density and reducing the risk of osteoporosis.
Key Strategies for Staying Strong After 40
- Prioritise Strength Training (2–3x per week): Focus on compound, functional movements that mimic daily life — squats (or sit-to-stands), lunges, rows, push-ups and deadlifts.
- Focus on Progressive Overload: Gradually increasing weight, repetitions or intensity ensures that muscles continue to adapt and strengthen over time.
- Incorporate Mobility and Flexibility: Include stretching, yoga or Tai Chi to keep joints lubricated, maintain range of motion and reduce stiffness.
- Increase Protein Intake: Protein requirements often increase with age due to reduced anabolic sensitivity. Aim for 1 to 1.2 grams of protein per kilogram of body weight, evenly distributed across meals, to support muscle repair.
- Consistency over Intensity: You do not need to lift like a bodybuilder to see benefits. Short, consistent weekly sessions are highly effective.
