Understanding the Muscle Composition Behind a 91-Year-Old Sprinting Phenomenon

A remarkable event took place when a 91-year-old woman broke the world record in the 200-meter sprint, running the race in 51.47 seconds—nearly 1.5 seconds faster than the previous record in her age category. This extraordinary feat has piqued scientific interest, prompting extensive research into her muscular and physiological characteristics.

Researchers from the University of Pavia in Italy and Marquette University in Milwaukee conducted a comprehensive study — dubbed Trajector-AGE — to investigate what makes her ability to run so swiftly at her advanced age possible. The study included cycling tests and knee extensor exercises to assess her muscle power output and endurance, complemented by muscle biopsies performed on her thigh.

Results revealed that her cardiorespiratory fitness was comparable to women in their 50s, indicating a highly efficient circulatory and respiratory system capable of supporting intense physical activity. Additionally, her mitochondrial function, responsible for energy production within cells, was on par with much younger women, highlighting preserved cellular energy capacity.

A key discovery was the exceptional size of her slow-twitch (Type I) muscle fibers. These fibers are known for their endurance and resistance to fatigue, enabling prolonged activity with minimal exhaustion. She also exhibited a high proportion of fast-twitch (Type II) muscle fibers, which generate quick, powerful movements suitable for sprinting and explosive activity.

According to Marta Colosio, Ph.D., the study's first author, this rare combination of muscle fiber qualities likely underpins her ability to perform at such a high level, maintaining both endurance and speed despite her age. Her case underscores the potential of lifelong exercise and physical activity in preserving muscle function.

The findings emphasize that physical activity is vital for healthy aging, even for those who haven't been lifelong exercisers. Regular exercise can significantly contribute to maintaining muscle mass, strength, and overall functional ability into older age, encouraging a more active lifestyle for healthy aging.

This case exemplifies that with proper muscle conditioning, exceptional athletic performances are possible well into old age, advocating for ongoing physical activity as a crucial component of aging healthfully.

Source: Medical Xpress