title: Improvement in knee extension strength through training by means of combined electrical stimulation and voluntary muscle contraction.
abstract: Weight training (WT) is the most common method of maintaining and increasing muscle strength. WT, however, is not always useful as it requires the external resistance and stabilization. We have developed a "hybrid training" (HYB) approach that avoids these problems by using electrically stimulated muscles to provide resistance to the motion of a muscle undergoing training. Here we report the efficacy of HYB compared with conventional WT for increasing the muscle strength around the knee at both slow and fast joint speeds (at 30 and 180 degrees /sec). Two matched groups, each of 8 healthy men aged 22 years, exercised 3 times/week for six weeks. Both groups showed significantly increased strength in concentric torque at 30 degrees /sec (HYB +28%, WT +33%) and at 180 degrees /sec (HYB +33%, WT +38%), and also in eccentric torque at 30 degrees /sec (HYB +25%, WT +24%) and at 180 degrees /sec (HYB +19%, WT +30%) (p < 0.001). HYB is comparable with WT exercising with the exception of high-speed contractions, while HYB has a clear advantage in not needing external resistance equipment or stabilization. HYB is therefore considered a useful approach for strengthening muscles when a person is restricted to bed rest or during space flight.
authors.affiliation: Rehabilitation Center, Kurume University, 67 Asahi-machi, Kurume City, Fukuoka 830-0011, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Iwasaki
authors.forename: Naoto
authors.initials: N
authors.lastname: Shiba
authors.forename: Hiroo
authors.initials: H
authors.lastname: Matsuse
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nago
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Umezu
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Tagawa
authors.forename: Kensei
authors.initials: K
authors.lastname: Nagata
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Basford
mesh_terms: D000328:Adult; D003131:Combined Modality Therapy; D004558:Electric Stimulation; D005081:Exercise Therapy / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007717:Knee / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D019415:Torque; D014891:Weight Lifting / Q000502:physiology*