Blood Flow Restriction Compared To High Intensity Interval Training On Body Composition And Tendon Width

Abstract

Blood flow restriction (BFR) is a low load exercise modality advocated to improve body composition. PURPOSE: To compare BFR against high intensity interval training (HIIT) body-weight squats (BWS), and 80% 1RM squats (CON) in body composition and quadriceps tendon cross section area (QXS). METHODS: Thirteen subjects participated in the study (27±5.8 years, BMI: 23.3±3.2, F:8). Subjects were randomly assigned to a BFR (n=5), HIIT (n=5), or CON (n=3). Body composition was measured via air plethysmography while QXS was measured via musculoskeletal ultrasound. Subjects were tested at baseline and 6-weeks after training. BFR bands were placed at the proximal thigh and inflated to 250mmHg while performing a 30/15/15/15 repetition (rep) protocol using a metronome (1 rep/2 secs). The HIIT group completed BWS during a 20 sec on and 10 sec off protocol for 8 sets. The control (CON) group completed 3 sets of 5 reps squats of their 80% 1RM. All three groups completed their workouts 3 times a week. Due to the small sample size Kruskall-Wallis (KW) was performed for the variables of fat mass (fm;kg), lean mass (lm;kg), and QXS (cm) during baseline. If no differences at baseline were found the same analysis was performed for the 6-week follow-up. In addition, a KW analysis between groups was performed for the difference between baseline and follow-up values between variables. RESULTS: Although BFR showed improvements (fm: -1.1 kg; lm: +0.3kg; QXS: + .01cm) for all variables over the other groups (HIIT: fm: +1.5kg, lm: -1.2kg, QXS: -.02cm; CON: fm: -.05kg, lm: +0.4, QXS: +0.1cm) none of the two KW analytical approaches showed a statistically significant difference for any of the variables of interest. CONCLUSION: Although BFR showed improvements in all variables, the magnitude of these changes was not significant enough to demonstrate it is a superior modality than HIIT or 80% 1 RM or 6-weeks of training is not sufficient time to elicit changes in these outcomes.