Neil A Segal1, Glenn N Williams2, Maria C Davis3, Robert B Wallace4, Alan E Mikesky5. 1. Department of Rehabilitation Medicine, The University of Kansas, Kansas City, KS(∗). Electronic address: segal-research@uiowa.edu. 2. Department of Physical Therapy & Rehabilitation Science; The University of Iowa, Iowa City, IA(†). 3. Department of Orthopaedics & Rehabilitation; The University of Iowa, Iowa City, IA(‡). 4. Department of Epidemiology; The University of Iowa, Iowa City, IA(§). 5. Department of Kinesiology; Indiana University-Purdue University Indianapolis, Indianapolis, IN(‖).
Abstract
OBJECTIVE: To assess whether concurrent blood flow restriction (BFR) during low-load resistance training is an efficacious and tolerable means of improving quadriceps strength and volume in women with risk factors for symptomatic knee osteoarthritis (OA). DESIGN: Randomized, double-blinded, controlled trial. SETTING: Exercise training clinical research laboratory. PARTICIPANTS: Women over age 45 years with risk factors for symptomatic knee OA. METHODS: Participants were randomized to either low-load resistance training (30% 1RM) alone (control) or with concurrent BFR and completed 4 weeks of 3 times per week leg-press resistance training. Those randomized to BFR wore a cuff that progressively restricted femoral blood flow over the weeks of training. Intergroup differences in outcome measures were compared using regression methods, while adjusting for BMI. MAIN OUTCOME MEASURES: Isotonic bilateral leg press strength, isokinetic knee extensor strength, and quadriceps volume by magnetic resonance imaging were assessed before and after participation. Secondary measures included lower limb muscle power (leg press and stair climb). Knee pain was assessed to determine tolerance. RESULTS: Of 45 women who consented to study participation, 40 completed the program. There were no significant intergroup differences in baseline characteristics except that body mass index was lower in the BFR group (P = .0223). Isotonic 1RM improved significantly more in the BFR group (28.3 ± 4.8 kg) than in the control group (15.6 ± 4.5 kg) (P = .0385). Isokinetic knee extensor strength scaled to body mass increased significantly more in the BFR group (0.07 ± 0.03 nm/kg) than in the control group (-0.05 ± 0.03 nm/kg) (P = .0048). Changes in quadriceps volume, leg press power, and knee-related pain did not significantly differ between groups. CONCLUSIONS: Addition of BFR to a 30% 1RM resistance training program was effective in increasing leg press and knee extensor strength in women at risk for knee OA, in comparison with the same program without BFR.
RCT Entities:
OBJECTIVE: To assess whether concurrent blood flow restriction (BFR) during low-load resistance training is an efficacious and tolerable means of improving quadriceps strength and volume in women with risk factors for symptomatic knee osteoarthritis (OA). DESIGN: Randomized, double-blinded, controlled trial. SETTING: Exercise training clinical research laboratory. PARTICIPANTS: Women over age 45 years with risk factors for symptomatic knee OA. METHODS:Participants were randomized to either low-load resistance training (30% 1RM) alone (control) or with concurrent BFR and completed 4 weeks of 3 times per week leg-press resistance training. Those randomized to BFR wore a cuff that progressively restricted femoral blood flow over the weeks of training. Intergroup differences in outcome measures were compared using regression methods, while adjusting for BMI. MAIN OUTCOME MEASURES: Isotonic bilateral leg press strength, isokinetic knee extensor strength, and quadriceps volume by magnetic resonance imaging were assessed before and after participation. Secondary measures included lower limb muscle power (leg press and stair climb). Knee pain was assessed to determine tolerance. RESULTS: Of 45 women who consented to study participation, 40 completed the program. There were no significant intergroup differences in baseline characteristics except that body mass index was lower in the BFR group (P = .0223). Isotonic 1RM improved significantly more in the BFR group (28.3 ± 4.8 kg) than in the control group (15.6 ± 4.5 kg) (P = .0385). Isokinetic knee extensor strength scaled to body mass increased significantly more in the BFR group (0.07 ± 0.03 nm/kg) than in the control group (-0.05 ± 0.03 nm/kg) (P = .0048). Changes in quadriceps volume, leg press power, and knee-related pain did not significantly differ between groups. CONCLUSIONS: Addition of BFR to a 30% 1RM resistance training program was effective in increasing leg press and knee extensor strength in women at risk for knee OA, in comparison with the same program without BFR.
Authors: Anthony Cuoco; Damien M Callahan; Stephen Sayers; Walter R Frontera; Jonathan Bean; Roger A Fielding Journal: J Gerontol A Biol Sci Med Sci Date: 2004-11 Impact factor: 6.053
Authors: Ashraf S Gorgey; Mark K Timmons; David R Dolbow; Justin Bengel; Kendall C Fugate-Laus; Lori A Michener; David R Gater Journal: Eur J Appl Physiol Date: 2016-05-07 Impact factor: 3.078
Authors: Thomas W Buford; Roger B Fillingim; Todd M Manini; Kimberly T Sibille; Kevin R Vincent; Samuel S Wu Journal: Contemp Clin Trials Date: 2015-06-23 Impact factor: 2.226
Authors: Peter Ladlow; Russell J Coppack; Shreshth Dharm-Datta; Dean Conway; Edward Sellon; Stephen D Patterson; Alexander N Bennett Journal: Pilot Feasibility Stud Date: 2017-12-08
Authors: Breanne S Baker; Michael S Stannard; Dana L Duren; James L Cook; James P Stannard Journal: Clin Orthop Relat Res Date: 2020-03 Impact factor: 4.755