New Study Shows Differences in VO2 Max Between Men and Women

A recent study reveals important differences in how men and women should approach age-related declines in aerobic capacity. VO2 max, or maximal oxygen uptake, is a crucial indicator of long-term health and longevity, as well as athletic performance. This study aims to fill the gap in data regarding women’s VO2 max and highlights some intriguing findings.

The Study and Its Findings

Researchers at the Federal University of São Paulo in Brazil conducted a study involving 147 women aged 20 to 70. The participants included 85 runners and 62 sedentary individuals. They were further divided into two age groups: younger (under 50) and older (over 50). The researchers measured their VO2 max using a progressive treadmill test, analyzed body composition with a DXA scan, and gathered information on their training and health habits. The results were published in Experimental Gerontology.

Key Insights from the Data

The study’s main findings were expected: runners had higher VO2 max than non-runners, and younger women had higher VO2 max than older women. However, a deeper look into the data revealed more significant patterns.

1. Absolute VO2 Max:
Absolute VO2 max measures the total volume of oxygen used per minute, typically expressed in liters per minute. While higher VO2 max indicates better fitness, it can be misleading when comparing individuals of different body sizes.

2. Relative VO2 Max:
To address body size differences, VO2 max can be expressed relative to body weight (milliliters of oxygen per kilogram). This method showed a more significant gap between runners and non-runners because non-runners generally had higher body weights. Relative VO2 max is a better indicator of fitness for activities like running.

3. VO2 Max and Lean Mass:
A third approach divided VO2 max by lean body mass (mainly muscle). This method highlights the importance of muscle in determining VO2 max. More muscle mass generally leads to a higher ability to consume oxygen, essential for aerobic energy production.

Why Body Composition Matters

VO2 max depends on both oxygen supply and demand. Traditionally, it was thought that oxygen supply (how quickly oxygen is delivered to muscles) was the primary factor. However, oxygen demand (how effectively muscles use oxygen) is equally important. Thus, muscle mass plays a crucial role in VO2 max.

Unexpected Findings

Contrary to previous data from men, the study found that both central factors (heart and circulatory system) and peripheral factors (muscle oxygen usage) decline at similar rates in women as they age. This suggests potential differences in how VO2 max declines in men and women. One possible explanation is higher levels of intramuscular adipose tissue (fat within muscles) in women, which increases with age and could affect VO2 max.

Age-Related VO2 Max Decline in Runners

The study also noted that runners experienced a steeper decline in VO2 max with age compared to non-runners. This might be due to a regression to the mean, where those starting with higher VO2 max levels see a more significant drop. It could also be because older runners tend to train less intensely than younger ones.

Conclusion

This study underscores the importance of considering gender differences when addressing age-related declines in aerobic capacity. For women, maintaining muscle mass and staying active are crucial for preserving VO2 max. These findings could lead to more tailored approaches to fitness and health maintenance for men and women.

For more details, you can read the full study in Experimental Gerontology.