High-intensity interval walking training is more effective in middle-aged and older men and women with low physical fitness

 

Mayuko Morikawa^1,2, Kazunobu Okazaki¹, Toshiaki Yamazaki^1,3, Hirokazu Gen-no^2,3

and Hiroshi Nose^1,2

¹Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto 390-8621, Japan; ²Jukunen Taiiku Daigaku Research Center, Matsumoto 390-8621, Japan; ³Kissei Comtec Co. Ltd., Matsumoto 390-1293, Japan

 

We examined in middle-aged and older people whether peak aerobic capacity (VO_2peak, ml/kg/min) was closely linked with lifestyle-associated diseases and whether high-intensity interval walking (IWT) was more effective in frail people. From April to September of 2005 and 2006 (4-mos), 246 men (M) and 580 women (W) (65±7 yr) performed IWT, repeating ≥5 sets of 3-min slow walking at 40% VO_2peak for walking followed by a 3-min fast walking ≥70% VO_2peak/ day for ≥4 days/wk. Before and after IWT, we measured VO_2peak, BMI, systolic (SBP) and diastolic (DBP) blood pressures, isometric knee extension (F_EXT) and flexion (F_FLX) forces (Nm/kg), and blood chemicals.  For analyses, 198 M and 468 W, who underwent the exam both before and after IWT, were equally divided into 3 groups, respectively, based on pre-training VO_2peak; low (L), medium (M), and high (H). On the pooled pre-training values from M and W, F_EXT, F_FLX, and HDL-C were lower while BMI, SBP, and blood glucose (BG) were higher in the order of L, M, and H.  After IWT, VO_2peak, F_EXT, and F_FLX increased while SBP, DBP, BMI, and BG decreased in all groups, but % changes in VO_2peak, F_FLX, DBP and BG were the highest in L with significant correlations with fast walking time/ wk. Thus, IWT was more effective in frail people.

 

Key words: high-intensity interval walking, physical fitness, older people