Age and running experience influence shock attenuation during human running

Abstract

Objective: This study examined the associations of age and running experience with shock attenuation during running, as age and experience may influence passive (body composition) and active (gait) shock attenuation mechanisms.

Design: Cross-sectional study.

Methods: Participants included healthy middle-aged-experienced runners (n = 20, age: 52.95 ± 5.83 years, >1 year of experience, 9-30 mi·week^-1), young-experienced runners (n = 24, age: 22.37 ± 4.09 years, >1 year of experience, 9-30 mi·week^-1), and young-novice runners (n = 14, age: 22.50 ± 3.52 years, <1 year of experience, 3-13 mi·week^-1). Participants ran overground at 3.35 m·s^-1 while triaxial accelerometers measured tibial and low-back impact shock. Frequency-domain axial and resultant shock attenuation was calculated using a transfer function within 3-8 Hz (FB1), 9-20 Hz (FB2), 21-35 Hz (FB3), and 36-50 Hz (FB4) bins. Linear regression tested associations of age among experienced runners and experience among young runners with each dependent variable (α > 0.05).

Results: Middle-aged-experienced runners attenuated less resultant shock within FB1 (p = 0.02, 95 % confidence interval: 1.27-18.71, β = 9.99) and axial shock within FB2 (p = 0.04, confidence interval: 0.40-37.37, β = 28.89) and FB3 (p = 0.005, confidence interval: 17.02-91.71, β = 54.37) than young-experienced runners. Young-novice attenuated less axial shock within FB3 than young-experienced runners (p = 0.02, confidence interval: 6.72-92.13, β = 49.43).

Conclusions: Age and running experience independently influence shock attenuation, suggesting different shock attenuation responses between runner sub-populations.

Keywords: Aging; Running biomechanics; Running exposure; Shock absorption; Spectral analysis.