Acute effects of blood flow restriction running warm-up on Achilles tendon morphology and function in basketball athletes

To determine the acute effects of blood flow restriction (BFR) running warmup on Achilles tendon morphology and function in basketball players in order to provide a theoretical basis for optimizing warm-up protocols for military personnel and athletes susceptible to Achilles tendon injuries.

Twenty-seven male basketball players were subjected and asked to participate in 3 different running warm-up protocols: low-speed running (LSR), high-speed running (HSR), and BFR combined with LSR (BFR-LSR). The acute changes in Achilles tendon morphology, mechanical properties, and functional performance across the 3 testing sessions were analyzed and compared.

Immediately after training, both HSR warm-up and BFR-LSR warm-up significantly improved Achilles tendon thickness, blood flow, stiffness, and gastrocnemius maximal voluntary isometric contraction (MVIC) when compared with LSR warmup (P<0. 05). No statistical differences were observed in above indicators between the BFR-LSR and HSR warm-ups (P>0. 05). 24 hours after training, compared with LSR warm-up, HSR warm-up still significantly improved Achilles tendon thickness, blood flow, stiffness, and gastrocnemius MVIC (P<0. 05). Although BFR-LSR warm-up did not show statistically significant differences in these parameters compared to LSR warm-up, it still demonstrated positive trends. Immediately and 24 h after training, no obvious difference were found in jump performance among the 3 warm-up protocols (P>0. 05), but, both BFR-LSR and HSR warm-ups exhibited superior performance than LSR warm-up.

Immediately after training, BFR-LSR warm-up demonstrates comparable effects to the HSR warm-up on improving Achilles tendon morphology and performance, as well as enhancing jump performance. However, its sustained and long-term effects require further investigation.