Recovery Kinetics Following Change of Direction Training

Study Overview
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Brief Summary
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This study aims at investigating the recovery kinetics of skeletal muscle damage, neuromuscular fatigue and performance following a single change of direction (COD) training session in competitive soccer players. The impact of COD degrees will be also examined by comparing a 45o vs. 90o COD training session. Ten male soccer players will perform a COD45 [A single training session including 2x(10x  27.6m) sprints with two 45o COD in each sprint], a COD90 [A single training session including 2x(10x  21.2m) sprints with two 90o COD in each sprint] and a Control trial (No intervention included, only daily measurements) in randomized, repeated measures, crossover design. Assessments related to skeletal muscle damage, neuromuscular fatigue and performance will be performed prior to training session and daily for three consecutive days post-training, in each trial.

Detailed Description
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Ten male soccer players will be included in this study. Participants will be initially informed about the aim of study as well as the associated risks and benefits and subsequently will provide their signed consent form. At baseline, they will undergo assessment of their anthropometrics (i.e. body mass and body height), body composition (by DXA), physical conditioning status [maximal oxygen consumption (VO2max), Yo-Yo Intermittent Endurance test level 2 and Yo-Yo Intermittent Recovery test level 2] and daily dietary intake. Thereafter, they will participate in two experimental trials and one control trial in a randomized, crossover, repeated measures design: i) COD45: Participants in this trial will perform a COD training session consisted of 2 sets of 10 x  27.6m sprints with two 45o COD in each sprint and a resting period of 16 sec and 2:20 min between sprints and sets, respectively, ii) COD90: Participants in this trial will perform a COD training session consisted of 2 sets of 10 x  21.2m sprints with two 90o COD in each sprint and a resting period of 16 sec and 2:20 min between sprints and sets, respectively, iii) Control: Participants in this trial will only participate in daily assessments to control for day to day variability in the depended variables (they will not receive any intervention). Prior to each trial, participants will provide a resting blood sample (for the determination of blood lactate, white blood cell count and creatine kinase activity) and undergo assessment of their delayed onset of muscle soreness (DOMS), maximal voluntary isometric contraction (MVIC), countermovement jump [will be assessed using two force platforms at 1000 Hz and electromyography instrumentation (EMG)], isokinetic peak torque of knee extensors and flexors (will be assessed on an isokinetic dynamometer), agility (will be assessed using the Illinois test), 10m and 30m sprint time (will be assessed by using light cells) and repeated sprint ability (5x30m sprints will be performed with 25 sec rest in-between). In COD45 and COD90 experimental trials, a blood sample will be collected immediately post-training for the determination of blood lactate concentration while assessment of DOMS, MVIC and countermovement jump will be performed at 1, 2 and 3 hours post-training. In all trials assessment of DOMS, MVIC, countermovement jump (CMJ), isokinetic peak torque, agility and sprinting performance as well as determination of creatine kinase activity and white blood cell count will be performed at 24, 48 and 72 hours post-training. A 7-day wash out period will applied between trials.

Official Title
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Recovery Kinetics Following Change of Direction (COD) Training in Soccer: Implications for Different COD Angles

Conditions
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Skeletal Muscle Damage

Intervention / Treatment
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* Other: COD45
* Other: COD90


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Soccer players participating in at least 5 training sessions per week and 1official match Participation at a competitive level for at least 4 years Free of musculoskeletal injuries No use of ergogenic supplements or medication Non-smokers Exclusion Criteria: Musculoskeletal injury Use of alcohol, caffeine and any type of ergogenic supplements or medication during the course of the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Participants in this arm will receive no intervention | |
| Experimental: COD45<br>Participants in this arm will participate in a COD training session consisted of 45 degrees changes of direction | Other: COD45<br>* Participants will perform 2 sets of 10 sprints. The total distance for each sprint will be 27.6 meters and will include two changes of direction of 45 degrees. The recovery time will be 16 seconds between sprints and 2.20 minutes between sets<br>|
| Experimental: COD90<br>Participants in this arm will participate in a COD training session consisted of 90 degrees changes of direction | Other: COD90<br>* Participants will perform 2 sets of 10 sprints. The total distance for each sprint will be 21.2 meters and will include two changes of direction of 90 degrees. The recovery time will be 16 seconds between sprints and 2.20 minutes between sets<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in creatine kinase activity | Creatine kinase activity will be measured in plasma | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in white blood cell count | White blood cell count will be measured by using an automatic blood analyzer | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in delayed onset of muscle soreness | Muscle soreness will be assessed by palpation of the muscle belly and the distal region | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in isometric peak torque | Isometric peak torque will be assessed on an isokinetic dynamometer | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in fatigue index of maximal voluntary isometric contraction during 10 seconds | Fatigue rate will be determined by calculating the percent drop of peak torque between the first and the last three seconds of a 10-second maximal isometric contraction | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in isokinetic peak torque of knee extensors | Isokinetic peak torque will be assessed on an isokinetic dynamometer in both limbs | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in isokinetic peak torque of knee flexors | Isokinetic peak torque will be assessed on an isokinetic dynamometer in both limbs | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in countermovement jump height | Countermovement jump height will be assessed by using two force platforms at 1000 Hz, with each foot in parallel on the two platforms providing a separate yet time-synchronized measurement of the jump height for each leg | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in ground reaction force during countermovement jump | Ground reaction force will be assessed by using two force platforms at 1000 Hz, with each foot in parallel on the two platforms providing a separate yet time-synchronized measurement of the jump height for each leg | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in peak power during countermovement jump | Peak power will be assessed using two force platforms at 1000 Hz, with each foot in parallel on the two platforms providing a separate yet time-synchronized measurement of the jump height for each leg | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in mean power during countermovement jump | Mean power will be assessed using two force platforms at 1000 Hz, with each foot in parallel on the two platforms providing a separate yet time-synchronized measurement of the jump height for each leg | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in vertical stiffness during countermovement jump | Vertical stiffness will be assessed using two force platforms at 1000 Hz, with each foot in parallel on the two platforms providing a separate yet time-synchronized measurement of the jump height for each leg | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in peak rate of force development during countermovement jump | Peak rate of force development will be assessed using two force platforms at 1000 Hz, with each foot in parallel on the two platforms providing a separate yet time-synchronized measurement of the jump height for each leg | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in peak normalized electromyography (EMG) during the eccentric and concentric phases of the countermovement jump | EMG data will be collected wirelessly at 2000 Hz using a Myon MA-320 EMG system (Myon AG, Switzerland) for the vastus lateralis, biceps femoris, gastrocnemius and gluteus maximus muscles. | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in mean normalized electromyography (EMG) during the eccentric and concentric phases of the countermovement jump | EMG data will be collected wirelessly at 2000 Hz using a Myon MA-320 EMG system (Myon AG, Switzerland) for the vastus lateralis, biceps femoris, gastrocnemius and gluteus maximus muscles. | At baseline, at 1, 2, 3, 24, 48 and 72 hours after change of direction training session | 
| Change in repeated sprint ability | Repeated sprint ability will be tested using 5x30 m sprints with 25 seconds rest in-between | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in sprint time of 10m | 10m sprint time will be assessed using light cells | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in sprint time of 30m | 30m sprint time will be assessed using light cells | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in agility | Agility will be assessed using the illinois agility test. | At baseline, at 24, 48 and 72 hours after change of direction training session | 
| Change in field activity during the change of direction training session | Field activity will be continuously monitored during the change of direction training session by using global positioning system (GPS) | During the change of direction training session | 
| Change in heart rate during the change of direction training session | Heart rate will be continuously monitored during the change of direction training session by using heart rate monitors. | During the change of direction training session | 
| Change in blood lactate concentration | Blood lactate will be measured using a lactate plus system | At baseline and immediately post change of direction training session | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body mass | Body mass will me measured on a beam balance with stadiometer | At baseline | 
| Body height | Body height will me measured on a beam balance with stadiometer | At baseline | 
| Body fat | Body fat will be assessed by using Dual-emission X-ray absorptiometry | At baseline | 
| Lean body mass | Lean body mass will be assessed by using Dual-emission X-ray absorptiometry | At baseline | 
| Maximal oxygen consumption (VO2max) | VO2max will be measured by open circuit spirometry via breath by breath method | At baseline | 
| Yo-Yo Intermittent Endurance Test level 2 performance |  | At baseline | 
| Yo-Yo Intermittent Recovery Test level 2 performance |  | At baseline | 
| Dietary intake | Dietary intake will be assessed over a 7-day period by using diet recalls | At baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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change of direction training, recovery, soccer, performance