title: Effects of macronutrient intake on thigh muscle mass during home-based walking training in middle-aged and older women.
abstract: We examined whether post-exercise macronutrient supplementation during a 5-month home-based interval walking training (IWT) accelerated exercise-induced increases in skeletal muscle mass and strength in healthy middle-aged and older women. Thirty-five women (41-78 years) were randomly divided into two groups: IWT alone (CNT, n = 18) or IWT plus post-exercise macronutrient (7.6 g protein, 32.5 g carbohydrate, and 4.4 g fat) supplementation (NUT, n = 17). For IWT, all subjects were instructed to repeat five or more sets of 3-min low-intensity walking at 40% peak aerobic capacity (Vo2 peak ), followed by a 3-min high-intensity walking above 70% Vo2 peak per day for 4 or more days per week. We determined Vo2 peak , thigh muscle tissue area by computer tomography, and thigh muscle strength in all subjects before and after IWT. We found that an increase in hamstring muscle tissue area was 2.8 ± 1.2% in NUT vs -1.0 ± 0.7% in CNT and that in isometric knee flexion force was 16.3 ± 3.7% in NUT vs 6.5 ± 3.0% in CNT; both were significantly higher in NUT than in CNT (both, P < 0.001). Thus, post-exercise macronutrient supplementation enhanced the increases in thigh muscle mass and strength, although partially, in home-based IWT in middle-aged and older women.
authors: Department of Sports Medical Sciences, Institute of Pathogenesis and Disease Prevention, Shinshu University Graduate School of Medicine, Matsumoto, Japan; Jukunen Taiiku Daigaku Research Center, Matsumoto, Japan.
authors: K
authors: K
authors: Okazaki
authors: D
authors: D
authors: Yazawa
authors: M
authors: M
authors: Goto
authors: Y-I
authors: YI
authors: Kamijo
authors: M
authors: M
authors: Furihata
authors: H
authors: H
authors: Gen-no
authors: K
authors: K
authors: Hamada
authors: H
authors: H
authors: Nose
mesh_terms: D000328:Adult; D000368:Aged; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007564:Japan; D007719:Knee Joint / Q000502:physiology*; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000254:growth & development* / Q000502:physiology; D010101:Oxygen Consumption; D013848:Thigh / Q000502:physiology; D016138:Walking / Q000502:physiology*
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins
keywords: carbohydrate; computer tomography; exercise; interval walking training; protein; thigh muscle strength