None listed
Conditions
Brief summary
The present pilot study aims to explore the effects of blood flow restriction (BFR) during low-load resistance training on knee flexor muscle fatigue in recreational athletes. As a pilot investigation, our specific objectives include assessing the feasibility of the study protocol, refining methodological approaches, and obtaining preliminary data on the potential impact of BFR on knee flexor muscle fatigue index and adverse events. Also, the pilot study serves as an initial step to assess the practicality of the research protocol, identify potential challenges, and estimate effect sizes for sample size calculations in future studies.
Interventions
Name of the intervention: blood flow restriction
Materials: For blood flow restriction purposes, a wireless lower limb blood flow restriction cuff with a length of 81 cm and a width of 10 cm will be used (AirBands, VALD Health, VALD Pty Ltd., Newstead QLD, Australia). Detailed information concerning the cuffs used in the study is available on the product's website: https://airbandsbfr.com.
Procedures: The cuff will be placed on the thigh of the dominant limb, at the level of the largest circumfe
Name of the intervention: blood flow restriction Materials: For blood flow restriction purposes, a wireless lower limb blood flow restriction cuff with a length of 81 cm and a width of 10 cm will be used (AirBands, VALD Health, VALD Pty Ltd., Newstead QLD, Australia). Detailed information concerning the cuffs used in the study is available on the product's website: https://airbandsbfr.com. Procedures: The cuff will be placed on the thigh of the dominant limb, at the level of the largest circumference, directly under the inguinal fold. Then, the examiner will ensure the module is facing forward, and the AirBands logo can be read the right way up. The examiner will fasten the cuff in the correct position by wrapping the cuff through the metal loop, ensuring enough room under the cuff for two fingers between the skin and the cuff and no residual air in the air bladder. Consecutively, the cuff will be paired with the AirBands App installed on the tablet (Galaxy Tab S7 SM-T870, Samsung Electronics Co., Ltd. 129, Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, Republic of Korea) via Bluetooth. Then, the cuff will be calibrated. The calibration will be carried out supine, with the relaxed knee supported on a half-moon bolster pillow. During calibration, the cuff will be inflated to automatically detect the maximal (100%) limb pressure and consecutively deflated. The intervention will be applied during low-load resistance training for knee flexors. The unilateral low-load resistance training for dominant limb knee flexors will be performed using the isokinetic dynamometer Biodex System 4 Pro (Biodex Medical Systems, Inc., Shirley, NY, USA. The length of the lever arm will be set at 40 cm. The trunk will be stabilized using belts. The arms of the participant will be crossed on his chest, and his head will be leaning on the chair. The foot of the trained limb will be in a neutral position. Three consecutive series of alternate concentric repetitions will be performed for the extension and flexion of the knee joint; however, the resistance will be applied only for knee flexion. The pre-defined resistance will exceed 30% of the maximal isometric torque measured on a previous occasion. The three series will comprise 30, 15, and 15 repetitions consecutively, with thirty-second-long breaks between consecutive series. Before baseline primary outcome measurement preceding the low-load resistance training for knee flexors, participants will perform a standardized warm-up on a cycle ergometer (12 minutes with a constant speed of 60 revolutions per minute and a constant load of 50 watts). Intervention provider: The examiner, a physiotherapist with over a decade of experience in clinical practice and research, is responsible for applying the blood flow restriction and conducting the low-load resistance training for knee flexors. She has extensive experience in applying blood flow restriction using specific cuffs and isokinetic dynamometers. Mode of delivery: face-to-face, individually. The number of times the intervention will be delivered: once. Duration of the intervention: through a single unit of the unilateral low-load resistance training for dominant limb knee flexors described above. Dose: The blood flow restriction cuff will be inflated to 80% of the maximal pressure detected during the calibration.
Sponsors
Wroclaw Medical University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
Male
Age
20 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
The inclusion criteria will be as follows: male; dominant right lower limb; age 20-30 years; lack of a history of injuries or diseases in lower limbs or lower back; no pain in lower limbs or lower back; no diagnosed systematic illnesses; sports activity on a recreational level; general good health; lack of any contraindications for blood flow restriction training, precisely any heart or vessels disorders, venous thromboembolism, antiphospholipid syndrome, family history of venous thromboembolism, thrombophilia, limb infection, diabetes mellitus, cancer, history of vascular transplantation, lymphoedema, antithrombin deficiency; Body Mass Index between 18.50 and 24.99; the bilateral full range of knee active motion; bilateral knee muscles strength exceeding grade 5 in Medical Research Council Scale; bilaterally negative results of all performed special tests; the between-limb differences in knee joint and thigh circumferences less than 2 cm.
Exclusion criteria
The exclusion criteria will be as follows: female; dominant left lower limb; younger than 20 years or older than 30 years old; history of injuries or diseases in lower limbs or lower back; the presence of pain in lower limbs or lower back; diagnosed systematic illnesses; sports activity on other than recreational level; presence of any contraindications for blood flow restriction training, precisely any heart or vessels disorders, venous thromboembolism, antiphospholipid syndrome, family history of venous thromboembolism, thrombophilia, limb infection, diabetes mellitus, cancer, history of vascular transplantation, lymphoedema, antithrombin deficiency; Body Mass Index lower than 18.50 or higher than 24.99; deficiency in knee active range of motion; deficiency in knee muscles strength according to Medical Research Council Scale; positive results of all performed special tests; the between-limb differences in knee joint and thigh circumferences larger than 2 cm.
Outcome results
None listed