[Exercise training with blood flow restriction : mechanisms and applications]. / Entraînement avec occlusion vasculaire: mécanismes et applications.

Traditional guidelines state that substantial muscle development requires training at least 70% of the one-repetition maximum (1RM) load. However, recent evidence has proven that low load training (20-40 % 1RM) combined with moderate blood flow restriction (BFR) can also lead to improvements in muscle mass and strength. While BFR has primarily been studied in clinical populations, emerging evidence demonstrates the effectiveness of BFR in sport. This article displays the mechanisms, methods, protocols, risks, and known effects of BFR.

Les directives traditionnelles stipulent qu'un développement musculaire nécessite un entraînement avec une charge minimale correspondant à 70 % du maximum d'une répétition (1RM). Cependant, des preuves récentes suggèrent que l'entraînement à faible charge (20-40 % de 1RM), combiné à une restriction modérée du flux sanguin (Blood Flow Restriction, BFR), peut également entraîner des améliorations de la masse et de la force musculaires. Alors que le BFR a d'abord été principalement étudié sur des populations cliniques, de nouveaux travaux rapportent son efficacité en milieu sportif. Cet article présente les mécanismes, les méthodes, les protocoles, les risques ainsi que les effets connus du BFR.

Combined Hip Abductor and External Rotator Strengthening and Hip Internal Rotator Stretching Improves Pain and Function in Patients With Patellofemoral Pain Syndrome: A Randomized Controlled Trial With Crossover Design.

BACKGROUND: Active rehabilitation has an important role in the management of patellofemoral pain syndrome (PFPS). Although some studies have shown the benefit of hip-muscle strengthening, the effect of combining hip-muscle stretching with strengthening has not yet been defined. PURPOSE: To evaluate the effect of combined strengthening of the hip external rotators and abductors and stretching of the hip internal rotators on pain and function in patients with PFPS. STUDY DESIGN: Randomized controlled trial; Level of evidence, 2. METHODS: A total of 109 patients with PFPS (75 female and 34 male; mean age, 31.6 ± 10.8 years) were first randomly assigned to protocol A (n = 67) of the A-B arm (AB group; standard rehabilitation) or protocol B (n = 42) of the B-A arm (BA group; standard rehabilitation with strengthening of the hip external rotators and abductors and stretching of the hip internal rotators). Each protocol consisted of 3 sessions a week for 4 weeks. After a washout period, corresponding to a symptom-free period, rehabilitation programs were crossed over. A visual analog scale (VAS) evaluating perceived pain, the Functional Index Questionnaire (FIQ), and the Kujala score were administered at baseline, the end of each rehabilitation protocol, and 12 weeks after the completion of the second protocol for each group. RESULTS: Until the final follow-up, VAS, FIQ, and Kujala scores were significantly improved in both the A-B and B-A arms (P < .05 for all). Compared with protocol A, protocol B provided significant improvement in terms of pain and function in both the BA (VAS and Kujala; P < .001) and AB (VAS and Kujala; P < .001) groups. CONCLUSION: Combined strengthening of the hip abductors and external rotators with stretching of the hip internal rotators provided better outcomes, which were maintained for at least 12 weeks, in terms of pain and function in patients with PFPS.