American pop icon Jennifer Lopez, 56, spoke candidly about how her fitness routine has evolved with age — and why she now prioritises lifting weights over excessive cardio. “I do a lot of weights now… Even if you are into cardio, and you want to be slim, or drop weight, muscle is the thing that burns fat, and as we get older, we lose the muscle, so we need to build the muscle to keep a youthful appearance,” she told CBS Mornings. Her statement reflects a growing shift in fitness conversations, especially for people in their 40s and 50s.
But how much of this is backed by science? According to Dr Pranav Ghody, Consultant Endocrinologist & Diabetologist, Hospitals, Central, muscle building in midlife is not just important — it is essential.
“After the age of 30, we begin to gradually lose muscle mass, and this decline accelerates after 50,” explains Dr Ghody. “Hormonal changes, reduced physical activity, and natural ageing all contribute to this process.” This age-related muscle loss, known as sarcopenia, can significantly impact long-term health, he adds.
“Maintaining muscle mass protects joints, improves balance, and reduces the risk of falls,” says Dr Ghody. “It also helps preserve independence and functional strength — things like climbing stairs,
“In simple terms, yes,” says Dr Ghody. “Muscle tissue is metabolically active, meaning it burns more calories at rest compared to fat tissue. The more lean muscle someone has, the higher their resting metabolic rate tends to be.”
However, he clarifies that muscle does not “magically melt fat.”
“It makes fat loss easier when combined with proper nutrition,” he explains. “Strength training also improves insulin sensitivity, which allows the body to use glucose efficiently instead of storing it as fat.”
One of the most frustrating aspects of ageing is unexplained weight gain — even when eating habits remain the same. “Loss of muscle slows down metabolism,” says Dr Ghody. “This means the body burns fewer calories at rest, making weight gain easier.”
Reduced muscle mass can also lead to fatigue, weakness, and a ‘softer’ body composition, as many describe. “Maintaining muscle supports better posture, a firmer appearance, and more stable energy levels,” he adds. “”
The learning, according to Dr Ghody, is clear: “As we age, lifting weights is not just about looking toned. It is about protecting metabolism, strength, and long-term health. Especially in women post-menopause, strength training becomes one of the most powerful tools to counter metabolic slowdown.”
