MedPath

Recovery Kinetics After Different Power Training Protocols (PTRecovery)

Not Applicable
Completed
Conditions
Core Exercises Training
Control Condition
Accentuated Eccentric Exercises Training
Structural Exercises Training
Interventions
Other: Structural exercises training
Other: Core exercises training
Other: Control trial
Other: Accentuated eccentric exercises training
Registration Number
NCT04847427
Lead Sponsor
University of Thessaly
Brief Summary

Muscle power is one of the most important parameters in almost every athletic action, expressing the ability of the human muscle to produce great amounts of force with the greatest possible speed. For enhancing their muscle power, athletes comprise several resistance training programs as part of their training. However, muscle power training comprises of eccentric muscle actions, which, especially when unaccustomed, can lead to exercise-induced muscle damage and deterioration of muscle performance. Nevertheless, despite the fact that muscle power training comprises eccentric muscle actions, and consequently can lead to muscle injury and muscle performance reduction during the following days, the recovery kinetics after acute muscle power training have not been adequately studied. However, information regarding the recovery of the muscles after a power training protocol, is critical for the correct design of a training microcycle, and the reduction of injury risk. The aim of the present study is to investigate the muscle injury provoked after acute muscle power training using three different power training exercise protocols. Additionally, the effect of these protocols on muscle performance and neuromuscular fatigue indices will be examined.

Detailed Description

Muscle power is one of the most important parameters in almost every athletic action, and expresses the ability of the human muscle to produce great amounts of force with the greatest possible speed. Thus, muscle power is critical for high performance in athletic actions such as jumping, throwing, change of direction and sprinting. For enhancing their muscle power, athletes comprise several resistance training programs as part of their training. Core exercises as well as Olympic lifting has been used in muscle power training. The loads that are applied regarding the accomplishment of the most favorable power production are varying. Training load of 0% 1RM has been reported to favor power production at the countermovement squat jump, while loads of 56% 1RM and 80% 1RM, favored the power production at squat and clean, respectively. In the recent years, accentuated eccentric training has been proposed as a new training method for the enhancement of muscle power. This method emphasizes in the eccentric component of the muscle contraction, and there is evidence supporting the greater production of muscle force after accentuated eccentric training compared with the typical resistance exercise training method. Taking the above into consideration, muscle power training comprises of eccentric muscle actions, and the magnitude of the eccentric component depends on the emphasis that is given on the concentric or eccentric action, respectively, of the muscles during the exercises. However, eccentric muscle action, especially when unaccustomed, can lead to exercise-induced muscle damage (EIMD). Although concentric and isometric exercise may also lead to muscle injury, the amount of damage after eccentric muscle contractions is greater. EIMD, amongst others, is accompanied by increased levels of creatine kinase (CK) into the circulation, increased delayed onset of muscle soreness (DOMS), reduction of force production, reduction of agility and speed. Despite the fact that muscle power training comprises eccentric muscle actions and consequently can lead to muscle injury and muscle performance reduction during the following days, the recovery kinetics after acute muscle power training protocols have not been adequately studied. However, information regarding the recovery of the muscles after a power training protocol is critical for the correct design of a training microcycle, and the reduction of injury risk.

The aim of the present study is to investigate the muscle injury provoked after acute muscle power training using three different power training exercise protocols. Additionally, the effect of these protocols on muscle performance and neuromuscular fatigue indices will be examined.

According to a preliminary power analysis, a number of 8 - 10 participants is needed for significant differences to be observed at the variables that will be examined (α = 0.90). Thus, 10 participants will be included at the present study.

The study will be performed in a randomized, cross over, repeated measures design. During their 1st - 4th visit, all participants will sign an informed consent (1st visit) after they will be informed about all the benefits and risks of the study and they will fill and sign a medical history form. Participants will be instructed by a dietitian how to record a 7-days diet recall to ensure that they do not consume in greater extent nutrients that may affect EIMD and fatigue (e.g. antioxidants, amino acids, etc.) and to ensure that the energy intake during the trials will be the same. Subsequently, participants will have to be familiarized with the exercises that will be used during the three power training protocols, as well as with the measurements that will be used for the evaluation of performance indices.

During the 5th, 6th, 7th and 8th visit, baseline assessments will be performed. Fasting blood samples will be collected in order to estimate muscle damage concentration markers. Assessment of body mass and body height, body composition, and aerobic capacity (VO2max), will be performed. Squat jump and countermovement jump will be performed on a force platform to assess jump height, ground reaction force, peak and mean power, vertical stiffness and peak rate of force development; at the same time, peak and mean normalized EMG during the concentric phase of the squat jump, and during eccentric and concentric phases of the counter movement jump, for the vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximum muscles will be assessed. The peak concentric, eccentric and isometric isokinetic torque of the knee flexors and knee extensors, in both limbs will be evaluated on an isokinetic dynamometer at 60°/sec. Maximal voluntary isometric contraction (MVIC) of the knee extensors at 65° in both limbs, as well as the fatigue rate during MVIC through the percent drop of peak torque between the first and the last three seconds of a 10-sec MVIC.

During their 9th visit, participants will be randomly assigned into one of the four different conditions of the study design: a) Core exercises protocol, b) Structural exercises protocol, c) Accentuated eccentric load exercises protocol, d) Control Condition. Prior to each experimental protocol, assessment of DOMS in the knee flexors and knee extensors of both limbs, as well as blood lactate assessment will be performed. Field activity will be continuously recorded during the sprint training protocols using global positioning system (GPS) technology. Heart rate will be continuously recorded during the sprint training protocols using heart rate monitors. Additionally, DOMS of knee flexors and knee extensors, peak concentric, eccentric and isometric isokinetic torque, squat and countermovement jump height, as well as ground reaction force, peak and mean power, vertical stiffness and peak rate of force development during squat and countermovement jump, alongside with peak and mean normalized EMG during the concentric phase of the squat jump, and during eccentric and concentric phases of the counter movement jump, for the vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximum muscles will be assessed immediately after, 24h, 48h and 72h after the end of the trial. MVIC of the knee extensors of both limbs, as well as the fatigue rate during MVIC will also be assessed at 1h, 2h and 3h, as well as 24h, 48h, and 72h (10th, 11th and 12th visit) after the end of the trial. Blood lactate will also be assessed at 4 min, while creatine kinase at 24h, 48h, and 72h after the end of the trial. The exact same procedure (13rd - 16th visit, 17th - 20th visit, 22nd - 24th visit) will be repeated for the remaining three conditions. A 7-day wash out period will be mediated between trials.

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
10
Inclusion Criteria
  • At least 1 year experience in strength exercises
  • Absense of musculoskeletal injuries (≥ 6 months)
  • Abstence from use of ergogenic supplements or other drugs (≥ 1 month)
  • Abstence from participation at exercise with eccentric component (≥ 3 days)
  • Abstence from alcohol and energy drings consumption before each experimental trial
Exclusion Criteria
  • Less than 1 year experience in strength exercises
  • Musculoskeletal injuries (≤ 6 months)
  • Use of ergogenic supplements or other drugs (≤ 1 month)
  • Participation at exercise with eccentric component (≤ 3 days)
  • Alcohol and energy drings consumption before the experimental trials

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Structural exercises trainingStructural exercises trainingParticipants will perform 4 structural (Olympic lifting) exercises
Core exercises trainingCore exercises trainingParticipants will perform 4 core exercises
Control trialControl trialParticipants will perform all the measurements that are comprised in the experimental conditions without performing any exercise protocol
Accentuated eccentric exercises trainingAccentuated eccentric exercises trainingParticipants will perform 4 exercises with eccentric loading
Primary Outcome Measures
NameTimeMethod
Change in isometric peak torqueBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Eccentric peak torque will be measured on an isokinetic dynamometer

Differences in field activity between the three different power training protocolsDuring each power training protocol

Field activity will be continuously recorded during the power training protocols using global positioning system (GPS) technology

Change in delayed onset of muscle soreness (DOMS) in the knee flexors (KF) and extensors (KE) of both limbsBaseline (pre), 4 minutes post-, 24 hours post-, 48 hours post-, 72 hours post-trial

Participants will perform three repetitions of a full squat movement, and rate their soreness level in knee flexors and extensors on a visual analog scale from 1 to 10 (VAS, with "no pain" at one end and "extremely sore" at the other), using palpation of the belly and the distal region of relaxed knee extensors and flexors.

Change in mean power during squat jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Mean power will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate, yet time-synchronized measurement of the jump height for each leg

Change in peak power during squat jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Peak power will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate, yet time-synchronized measurement of the jump height for each leg

Change in vertical stifness during squat jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Vertical stifness will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate, yet time-synchronized measurement of the jump height for each leg

Change in countermovement jump heightBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Countermovement jump height will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate yet time-synchronized measurement of the jump height for each leg

Change in ground reaction force (GRF) during countermovement jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Ground reaction force will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate yet time-synchronized measurement of the jump height for each leg

Change in peak rate of force development during countermovement jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Vertical stifness will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate yet time-synchronized measurement of the jump height for each leg

Change in eccentric peak torqueBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Eccentric peak torque will be measured on an isokinetic dynamometer

Change in maximal voluntary isometric contraction (MVIC) during 10 secondsBaseline (pre), 1 hour post-, 2 hours post-, 3 hours post-, 24 hours post-, 48 hours post-, 72 hours post-trial

MVIC will be measured on an isokinetic dynamometer

Change in fatigue rate during maximal voluntary isometric contraction (MVIC)Baseline (pre), 1 hour post-, 2 hours post-, 3 hours post-, 24 hours post-, 48 hours post-, 72 hours post-trial

Fatigue rate during MVIC will be estimated through the percent drop of peak torque between the first and the last three seconds of a 10-second maximal isometric contaction

Change in heart rate between the three different power training protocolsDuring each power training protocol

Heart rate will be continuously recorded during during the power training protocols using heart rate monitors

Change in peak normalized EMG during the concentric phase of the squat jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Electromyography data will be collected wirelessly at 2000Hz using a Myon MA-320 EMG system (Myon AG, Schwarzenberg, Switzerland) for the vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximum muscles.

Change in mean normalized EMG during the concentric phase of the squat jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Electromyography data will be collected wirelessly at 2000Hz using a Myon MA-320 EMG system (Myon AG, Schwarzenberg, Switzerland) for the vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximum muscles.

Change in peak power during countermovement jump testBaseline (pre), post-, 24h post-, 48h post-, 72h post-trial

Peak power will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate yet time-synchronized measurement of the jump height for each leg

Change in vertical stifness during countermovement jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Vertical stifness will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate yet time-synchronized measurement of the jump height for each leg

Change in CK in bloodBaseline (pre), 4 minutes post-, 24 hours post-, 48 hours post-, 72 hours post-trial

Creatine kinase will be measured in plasma using a biochemical analyzer

Change in squat jump heightBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Squat jump height will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate, yet time-synchronized measurement of the jump height for each leg

Change in ground reaction force (GRF) during squat jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

GRFwill be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate, yet time-synchronized measurement of the jump height for each leg

Change in mean power during countermovement jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Mean power will be measured using two force platforms at 1000Hz, with each foot in parallel on the two platforms providing a seperate yet time-synchronized measurement of the jump height for each leg

Change in peak normalized EMG during the eccentric and concentric phases of the countermovement jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Electromyography data will be collected wirelessly at 2000Hz using a Myon MA-320 EMG system (Myon AG, Schwarzenberg, Switzerland) for the vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximum muscles.

Change in blood lactateBaseline (pre), 4 minutes post-trial

Blood lactate will be measured in capillary blood with a hand-portable analyzer

Change in mean normalized EMG during the eccentric and concentric phases of the countermovement jump testBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Electromyography data will be collected wirelessly at 2000Hz using a Myon MA-320 EMG system (Myon AG, Schwarzenberg, Switzerland) for the vastus lateralis, biceps femoris, gastrocnemius, and gluteus maximum muscles.

Change in concentric peak torqueBaseline (pre), 24 hours post-, 48 hours post-, 72 hours post-trial

Concentric peak torque will be measured on an isokinetic dynamometer

Secondary Outcome Measures
NameTimeMethod
Lean body massBaseline

Lean body mass will be measured by using Dual-emission X-ray absorptiometry

Dietary intakeBaseline

Dietary intake will be assessed using 7-day diet recalls

Body mass index (BMI)Baseline

BMI will be calculated from the ratio of body mass/ body height squared

Body weightBaseline

Body weight will be measured on a beam balance/stadiometer

Body fatBaseline

Body fat will be measured by using Dual-emission X-ray absorptiometry

Body heightBaseline

Body height will be measured on a beam balance/stadiometer

Maximal oxygen consumption (VO2max)Baseline

Maximal oxygen consumption will be measured by open circuit spirometry via breath by breath method

Trial Locations

Locations (1)

Chariklia K. Deli

🇬🇷

Trikala, Thessaly, Greece

© Copyright 2025. All Rights Reserved by MedPath