Effect of a prior bout of preconditioning exercise on muscle damage from downhill walking
Abstract
This study investigated whether reduced-duration downhill walking (DW) would confer a protective effect against muscle damage induced by a subsequent bout of longer duration DW performed 1 week or 4 weeks later. Healthy young adults were allocated to a control or one of the preconditioning exercise (PRE-1wk or PRE-4wk) groups (10 men and 4 women per group). PRE-1wk and PRE-4wk groups performed 20-minDW(–28% slope, 5 km/h, 10% body mass added to a backpack) 1 week and 4 weeks before 40-min DW, respectively, and the control group performed 40-min DW only. Maximal voluntary contraction (MVC) knee extension torque, plasma creatine kinase (CK) activity, and muscle soreness (100-mm visual analog scale) were measured before, immediately after, and 24, 48, and 72 h after DW, and the changes in these variables were compared among groups. The control group showed symptoms of muscle damage (e.g., prolonged decrease in MVC: –14% ± 10% at 48 h post-DW) after 40-min DW. Changes in all variables after 40-minDWof PRE-1wk and PRE-4wk groups were 54%–61% smaller (P < 0.05) than the control group, without significant differences between PRE-1wk and PRE-4wk groups for MVC and plasma CK activity. Importantly, changes after the preconditioning exercise (20-min DW) were 67%–69% smaller (P < 0.05) than those after the 40-min DW of the control group. These findings suggest that 20-min DW resulting in minor muscle damage conferred a protective effect against subsequent 40-min DW, and its effect could last for more than 4 weeks.
Keywords
Creatine kinase activity, Eccentric exercise, Hiking, Knee extensors, Maximum strength, Muscle soreness, Protective effect, Trekking
Document Type
Journal Article
Date of Publication
2015
Publisher
National Research Council of Canada
School
School of Medical and Health Sciences / Centre for Exercise and Sports Science Research
RAS ID
20646
Copyright
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Comments
Maeo, S., Ochi, Y., Yamamoto, M., Kanehisa, H., Nosaka, K. (2015). Effect of a prior bout of preconditioning exercise on muscle damage from downhill walking in Applied Physiology, Nutrition and Metabolism, 40(3), 274-279. Available here.