⏳ Study identifies the precise age when our bodies begin to age

Our bodies begin their physical decline earlier than is generally believed, but it remains possible to favorably influence this trajectory. A Swedish investigation spanning nearly half a century provides specific insights into this phenomenon.

Researchers at the Karolinska Institutet tracked several hundred individuals from adolescence to adulthood over a period of 47 years. Their aim was to map the evolution of physical fitness, muscle strength, and endurance over a lifetime. The data obtained, published in the Journal of Cachexia, Sarcopenia and Muscle, represents an exceptional longitudinal follow-up.


This research is based on repeated measurements of the same individuals, an approach that represents an advance compared to studies that simply compare different age groups at a single point in time. It allows observation of each participant's personal evolution over the decades, painting a more faithful picture of the reality of physical aging.

The data indicates a significant turning point around age 35. From this age, performance generally begins to decline, a trend that intensifies over time. This decrease appears to be a natural process affecting all individuals, regardless of their previous level of activity. This turning point corresponds to a period when physical development is complete and mechanisms related to aging begin subtly. This gradual decline is associated with physiological changes, such as a slight decrease in muscle mass and cardiovascular efficiency beginning to diminish.

However, the investigation delivers very positive news. Adults who choose to increase their activity, even after age 35, can see their capabilities improve by 5 to 10 percent. Maria Westerståhl, who leads this work, indicates that exercise helps slow the loss of performance, although it does not stop it completely. Her team now seeks to identify the factors, such as hormonal or genetic parameters, that would explain this peak observed at age 35 and to clarify the effect of movement on the body.

The participants, who will soon be re-examined, will help refine the understanding of the links between physical fitness, lifestyle, and health. The continuation of the study could thus identify the biological mechanisms at play and guide advice for healthy aging.

How does physical activity influence our body as we age?

Regular physical activity affects the body on multiple levels, particularly with advancing age. It stimulates the cardiovascular system, improves blood circulation, and helps the heart work more efficiently. These effects are beneficial for endurance and reduce the feeling of fatigue during daily efforts.

Regarding muscles, exercise promotes the maintenance of mass and strength. It encourages fiber regeneration and optimizes coordination between muscles and nerves. This allows movements to be performed with greater ease and preserves autonomy, especially for actions like carrying loads or climbing stairs.

The benefits are not limited to musculature. Regular activity also supports bone strength, joint flexibility, and contributes to the proper functioning of cognitive abilities. It can also contribute to better balance and a reduced risk of falls, an important aspect for older adults.

These advantages explain why, even when started late, physical activity provides measurable gains. It does not erase the decline, but favorably modifies its curve, thus offering a better quality of life in the long term.