title: Combined effects of low-intensity blood flow restriction training and high-intensity resistance training on muscle strength and size.
abstract: We investigated the combined effect of low-intensity blood flow restriction and high-intensity resistance training on muscle adaptation. Forty young men (aged 22-32 years) were randomly divided into four groups of ten subjects each: high-intensity resistance training (HI-RT, 75% of one repetition maximum [1-RM]), low-intensity resistance training with blood flow restriction (LI-BFR, 30% 1-RM), combined HI-RT and LI-BFR (CB-RT, twice-weekly LI-BFR and once-weekly HI-RT), and nontraining control (CON). Three training groups performed bench press exercises 3 days/week for 6 weeks. During LI-BFR training sessions, subjects wore pressure cuffs on both arms that were inflated to 100-160 mmHg. Increases in 1-RM were similar in the HI-RT (19.9%) and CB-RT (15.3%) groups and lower in the LI-BFR group (8.7%, p < 0.05). Maximal isometric elbow extension (MVC) increased in the HI-RT (11.3%) and CB-RT (6.6%) groups; there was no change in the LI-BFR group (-0.2%). The cross-sectional area (CSA) of the triceps brachii (TB) increased (p < 0.05) in the HI-RT (8.6%), CB-RT (7.2%), and LI-BFR (4.4%) groups. The change in relative isometric strength (MVC divided by TB CSA) was greater (p < 0.05) in the HI-RT group (3.3%) than in the LI-BFR (-3.5%) and CON (-0.1%) groups. Following training, relative dynamic strength (1-RM divided by TB CSA) was increased (p < 0.05) by 10.5% in the HI-RT group and 6.7% in the CB-RT group. None of the variables in the CON group changed. Our results show that low-intensity resistance training with BFR-induced functional muscle adaptations is improved by combining it with HI-RT.
authors.affiliation: Department of Human and Engineered Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, Japan. yasuda@h.k.u-tokyo.ac.jp
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Yasuda
authors.forename: Riki
authors.initials: R
authors.lastname: Ogasawara
authors.forename: Mikako
authors.initials: M
authors.lastname: Sakamaki
authors.forename: Hayao
authors.initials: H
authors.lastname: Ozaki
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Sato
authors.forename: Takashi
authors.initials: T
authors.lastname: Abe
mesh_terms: D000328:Adult; D001132:Arm / Q000098:blood supply; D003250:Constriction; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000098:blood supply* / Q000502:physiology; D009929:Organ Size; D010806:Physical Education and Training / Q000379:methods*; D010807:Physical Endurance / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology*; D055070:Resistance Training / Q000379:methods*; D055815:Young Adult