Human physical capabilities peak around age 35 and begin to decline shortly thereafter, according to a decades-long study that also indicated that starting to exercise, even later in life, can be beneficial for overall health.
Researchers emphasize that while fitness, strength, and muscle endurance may change after this age, it's never too late to start exercising.
Studies have shown that muscle tissue function can decline significantly in the sixth decade of life, impacting an individual's ability to live independently.
Until now, researchers have relied on studies conducted at specific points in time with selected participants.
In contrast, the recent study conducted by the Karolinska Institute in Sweden followed more than 400 randomly selected men and women born in 1958 for 47 years, regularly measuring their fitness and strength from ages 16 to 63. The findings show that physical fitness and strength begin to decline as early as age 35, regardless of the amount of training.
According to the study, reported by The Independent and published in the journal *Cascading, Sarcopenia, and Muscles*, after age 35, a gradual decline in physical ability occurs, accelerating with age.
The scientists wrote, "The rate of decline was initially small, but increased with age in both sexes, with no difference between them." They added, "The overall decline in physical ability from peak to age 63 ranged between 30 percent and 48 percent."
These findings provide new insights into how physical ability changes over time. The scientists say they also align with similar results previously observed in elite athletes.
The researchers wrote, “This reinforces the concept that a decline in physical ability can be observed before age 40, which may later lead to clinically significant physical impairment, particularly in individuals with a sedentary lifestyle.”
However, the researchers added, “It’s never too late to start moving.”
The scientists noted that even study participants who began physical activity in adulthood saw improvements in their physical ability ranging from 5 to 10 percent.
“Our study shows that physical activity can slow the decline in performance, even if it cannot completely stop it,” said Maria Westerstoll, the study’s lead author.
In future studies, the researchers hope to uncover the mechanisms behind why humans reach their peak performance around age 35 and “why physical activity can slow the decline in performance, but not stop it entirely.”
The scientists also hope to continue the study next year with the same participants, who will then be 68 years old, in an effort to find links between physical ability and lifestyle, health, and biological mechanisms.