How Fitness Changes As We Age
A long-running study led by Sweden’s Karolinska Institutet is shedding more light on how fitness, strength, and muscle endurance change throughout adulthood. Part of the Swedish Physical Activity and Fitness study, it followed several hundred participants ages 16 to 63 for 47 years, measuring their physical performance over time rather than relying on snapshot comparisons between different age groups.
The researchers found that physical performance — including cardiovascular fitness and muscular strength — begins to decline around age 35, regardless of how active or well-trained people are earlier in life. After this point, the decline continues gradually and accelerates with older age. However, the results also highlight that physical activity remains beneficial at any stage of adulthood. Participants who increased activity levels later in life improved their physical capacity by approximately 5 to 10 percent, demonstrating that exercise can meaningfully slow age-related decline even if it can’t fully prevent it. The results suggest that it’s never too late to become physically active, noting that while exercise cannot stop the natural aging process, it does help preserve function and delay performance loss.
Try this recipe today: Stir-Fried Eggplant With Honey, Turmeric & Soy
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