Effects of walking on epigenetic age acceleration: a Mendelian randomization study

Area of Science:

• Genetics and Epigenetics
• Aging Research
• Public Health & Exercise Science

Background:

• Walking is a primary physical activity linked to aging and physical function.
• The direct causal relationship between walking and aging is not well understood.
• Epigenetic clocks are key biological markers for assessing biological age.

Purpose of the Study:

• To investigate the causal impact of walking on epigenetic age acceleration (EAA).
• To explore the relationship between walking pace and biological aging.
• To determine if faster walking speed is associated with slower biological aging.

Main Methods:

• A two-sample, two-way Mendelian randomization (MR) study design was employed.
• Data on walking and leisure sedentary behavior were sourced from UK Biobank.
• Epigenetic age acceleration data were collected from 28 independent cohorts.

Main Results:

• A faster usual walking pace was significantly associated with delayed epigenetic aging across four key epigenetic clocks (GrimAge, PhenoAge, Horvath, Hannum).
• The association between walking pace and delayed EAA remained consistent across various MR analyses and sensitivity tests.
• No significant causal relationships were found between walking duration or frequency and EAA.

Conclusions:

• Increased usual walking pace is causally linked to a deceleration of epigenetic aging.
• Faster walking speed may contribute to a slower biological aging process.
• The findings highlight the importance of walking pace as a modifiable factor in aging.