Optimisation of Eccentric Exercises (OPTIMEX)

Characterization of the Endocrine Response to Exercise: Impact of the Muscle Contraction Modality

Regular physical activity is an important public health lever and is recognised as an alternative in the management of certain long-term conditions. To achieve beneficial effects on the body, exercise recommendations are based on several parameters such as duration, intensity and continuous or intermittent nature of the activity. However, the mode of muscle contraction during exercise is generally little considered or poorly defined in these recommendations, which can lead to prescribing errors. In particular, the eccentric contraction modality, which can be found in actions designed to slow down movement (e.g. walking downhill), represents an interesting strategy, but its prescription modalities are still poorly understood.

The beneficial effects of physical activity are based in part on the release of molecules (myokines) by the skeletal muscles during exercise, which improve the functioning of the body. However, the effect of downhill walking on the release of myokines by the muscle has been little studied. The lack of knowledge of this effect is therefore an obstacle to the use of this exercise modality to try to optimise physical activity recommendations for health or performance improvement.

The aim of this study is therefore to better understand how downhill walking (eccentric muscle contraction) affects the production of molecules by muscles (myokines) during exercise.

Study Overview

• Status: Recruiting
• Conditions: Healthy Control Subjects
• Intervention / Treatment: Device: Experimental: downhill treadmill walking at -10% and -20% gradient

Detailed Description

After being informed of the aims, nature and possible risks of the study, written informed consent will be obtained from the subjects.

Prior to enrolment, volunteers will undergo a medical evaluation that includes a review of personal and family medical history, any current medications, and a standard physical examination. Compliance with the inclusion/exclusion criteria will be checked during this examination.

After enrolment, subjects will perform a treadmill familiarization session.

Experimental days:

• Subjects will complete a 45-minute walking exercise on a negative gradient treadmill (6 km/h) in a randomised 2-way cross-over design with either a -10% or -20% gradient.
• Blood will be sampled immediately pre-exercise, 1-h and 24-h post-exercise for the analysis of muscle myokines.
• Exercise-induced muscle fatigue in lower limbs will be evaluated using squat and counter-movement jumps immediately before and post-exercise.
• Heart-rate variability will be measured during the eccentric exercise session.
• Thigh muscle volume will be measured immediately before and post-exercise.
• Exercise-induced myalgia at 24-, 48-, 72- and 96h will be assessed using a visual analogue scale.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Lise Laclautre; Phone Number: 334.73.754.963; Email: promo_interne_drci@chu-clermontferrand.fr
• Study Contact Backup: Name: Fabrice Rannou; Email: fabrice.rannou@uca.fr

Study Locations

• France
  • Clermont-Ferrand, France
    • Recruiting
    • Chu Clermont Ferrand
    • Contact: Lise LACLAUTRE; Email: promo_interne_drci@chu-clermontferrand.fr
    • Principal Investigator: Fabrice Rannou

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Body Mass Index between 18.5 and 24.9 kg/m² (18.5 ≤ BMI ≤ 24.9)
• Non-smoker
• No treatment (background or at the time of the examination)
• Physical check up considered compatible with study participation (no bones, articular or muscular problems in lower limbs)
• Subjects considered healthy by investigator based on medical questioning and clinical examination
• Affiliation to the French Social Security system
• Person who has read and understood the research-related information, and signed the consent forms

Exclusion Criteria:

• Smoking
• Subjects with heart or respiratory failure
• Participants with lower extremity injury in the past three months
• Contraindication to the application of a magnetic field (wearing a pacemaker, presence of prosthetic material or ferromagnetic foreign bodies, presence of cochlear implants or ocular prosthetic material)
• Participant that does not wish to participate (refusal to sign the consent form)
• Patients under guardianship, trusteeship, deprived of liberty or safeguard of justice

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: downhill treadmill walking -10% gradient; The subjects will perform downhill walking at 6 km/h for 45 min on a treadmill (-10% incline)	Device: Experimental: downhill treadmill walking at -10% and -20% gradient; The subjects will perform downhill walking at 6 km/h for 45 min on a treadmill (-10% or -20% incline)
Experimental: downhill treadmill walking -20% gradient; The subjects will perform downhill walking at 6 km/h for 45 min on a treadmill (-20% incline)	Device: Experimental: downhill treadmill walking at -10% and -20% gradient; The subjects will perform downhill walking at 6 km/h for 45 min on a treadmill (-10% or -20% incline)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of eccentric exercise on myokine concentrations	Changes in systemic myokine levels following submaximal downhill treadmill exercise at different inclines, at the same speed and for the same duration.	Blood sample at baseline (prior exercise), Hour 1 and Hour 24 post-exercise
Effect of treadmill inclination on myokine concentrations	Differences in systemic myokine levels concentrations following -10 and -20% gradient submaximal downhill treadmill exercises, at the same speed and for the same duration.	Blood sample at baseline (prior exercise), Hour 1 and Hour 24 post-exercise

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessment of exercise-induced muscle fatigue in lower limbs	squat jump	Baseline (prior exercise) and 15 seconds post-exercise
Assessment of exercise-induced muscle fatigue in lower limbs	counter-movement jump	Baseline (prior exercise) and 15 seconds post-exercise
Assessment of autonomic nervous system function	Heart rate variability (HRV) analysis Temporal and spectral analyses of cardiac variability	During treadmill exercise
Effect of treadmill exercise on muscle volume	Measurement of thigh and calf circumferences	Baseline (prior exercise) and 15 seconds post-exercise
Effect of treadmill exercise on muscle pain	Measurement of muscle pain induced by a half-squat movement (self-measurement by the subject using a visual analogic scale, 0-10)	Baseline (prior exercise) and 15 seconds post-exercise
Effect of treadmill exercise on delayed onset muscle soreness	Measurement of muscle pain induced by eccentric exercise (self-measurement by the subject using a visual analogic scale, 0-10)	Baseline (prior exercise) and Hour 24, Hour 48, Hour 72, Hour 96 post-exercise

Collaborators and Investigators

• Sponsor: University Hospital, Clermont-Ferrand

Study record dates

Study Major Dates

• Study Start (Actual): May 4, 2023
• Primary Completion (Estimated): June 1, 2024
• Study Completion (Estimated): December 1, 2024

Study Registration Dates

• First Submitted: June 23, 2023
• First Submitted That Met QC Criteria: December 21, 2023
• First Posted (Actual): January 5, 2024

Study Record Updates

• Last Update Posted (Actual): January 11, 2024
• Last Update Submitted That Met QC Criteria: January 9, 2024
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: RBHP 2022 RANNOU

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No