The Impact of Blood Flow Restriction Within Warm-up.
Condition: Healthy
Study type: Interventional

Summary: 
      Sixty athletes will be randomized in two groups; (1) an experimental group and (2) a control
      group. Both groups will undergo the following procedure:

      Moment 1:

        1. Baseline testing: countermovement jump, 25m sprint and strength assessment of the
           Hamstrings and Quadriceps muscle.

        2. Short warm-up (approximately 4 minutes), which will be completed with blood flow
           restriction cuffs (experimental group) or without (control group)

        3. Post testing: same tests as performed in baseline.

      Moment 2:

        1. Baseline testing: stiffness measurements of the Biceps Femoris Long Head via Shear Wave
           Elastography.

        2. Short warm-up (approximately 4 minutes), which will be completed with blood flow
           restriction cuffs (experimental group) or without (control group)

        3. Post testing: same tests as performed in baseline.

      Both moments of testing as well as the order in which the performance tests take place are
      randomized.
    

Detailed description: 
      Traditionally, athletes perform a warm-up program before participating in sport activities,
      due to its assumed beneficial effect on performance and injury prevention. However, within
      team sports, substitutes usually do not perform the comprehensive pre-match warm-up. In many
      cases, those substitute players get a very short period of time, during the game, to prepare
      themselves for coming on to the pitch where they immediately have to perform at a very
      high-intensity. Hence, this could lead to a poorer performance and a greater injury risk for
      those substitute players, as they did not get a decent warm-up.

      Therefore, new techniques are needed in order to prepare the substitute athletes optimally in
      a very short period of time (often within a few minutes). Consequently, the aim of this study
      is to investigate whether the incorporation of Blood Flow Restriction (BFR) within a warm-up
      routine could be of additional value. Both performance parameters and muscle stiffness will
      be evaluated. As Hamstring strain Injuries (HSI) are common within sports encompassing
      high-speed running, this muscle group will be investigated on muscle stiffness as a
      representation of the interventional effect on muscle stiffness. Athletes will be randomized
      in two groups of 30 participants (anticipated); (1) an experimental group and (2) a control
      group. Both groups will perform baseline testing (5x Countermovement Jump, 25m Sprint and
      Muscle Strength of hamstrings and Quadriceps), and a short warm-up program, followed by
      repeating the same tests as executed in baseline. The experimental group will receive Blood
      Flow Restriction within the warm-up routine, whereas the control group will do the same warm
      up program but without BFR.

      On a separate occasion, the same athletes will perform the same warm-up routine with a Shear
      Wave Elastographic assessment of the Biceps Femoris Long Head before and after (immediately
      after, after 5 minutes and once more after 10 minutes) the warm-up.
    

Intervention name(s): Warm-up + Blood Flow Restriction cuff (smart-cuff pro device, acting as pressurized tourniquet); Warm-up
Intervention type(s): Device; Other
Intervention description(s): Blood Flow Restriction; Warm-up without any special intervention (no Blood Flow Restriction)
Other intervention name(s): Kaatsu; partial vascular occlusion
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Prevention
Keywords: Shear Wave Elastography; Blood Flow Restriction; Warm-up; Performance