Effects of Mode of Contraction on Neuromuscular Fatigue

Summary

Aging is associated with multiple deteriorations of the neuromuscular system. Given the increase in life expectancy, the investigators can now distinguish old adults (\>60 years old) who conserve their neuromuscular capacities with regular physical activity and very old adults (\>80 years old) who suffer from an inexorable decline, even if the number of octogenarians and their quality of life are progressively increasing. However, the most part of the literature on fatigue and neuromuscular capacity with aging focused on isometric tasks. The results showed a significant decrease in maximal force production capacity and a greater resistance to fatigue for old people compared to the young population. When fatigue is induced trough dynamic contractions, greater fatigability was observed in old adults compared to young adults. Investigations performed on the population aged over 80 years old are rare, showing greater fatigability in octogenarians than old men (aged 60-80 years old) during isometric tasks. The knowledge about the effects of dynamic contractions in this population are limited, and performed uniquely in single leg isokinetic mode. Evaluations that require the use of both legs and higher muscle mass involved in the task (cycloergometer) are needed. Understanding neuromuscular fatigue and fatigability across different exercise modalities is necessary to set adapted physical activity programs aimed to maintain autonomy in older individuals.

Conditions

• Volunteers

Interventions

BEHAVIORAL

Mini Mental State Examination

test for evaluating a person's cognitive functions and memory capacity

DIAGNOSTIC_TEST

6 Minutes Walk Test

a standardized test of an individual's functional ability that involves walking the greatest distance a person can walk in six minutes. This walking may be limited by shortness of breath or fatigability.

DIAGNOSTIC_TEST

Timed up and go

A simple test used to assess a person's mobility and requires both static and dynamic balance. It uses the time it takes for a person to get up from a chair, walk three metres, turn around, walk to the chair and sit down.

DIAGNOSTIC_TEST

Isokinetic Body weight-based quadriceps intermittent fatigue test (BW-QIF Test)

The BW-QIF test is an interval incremental contraction test including blocks of discontinuous 100-s effort. Neuromuscular evaluation of the knee extensors between blocks (duration 25 s) includes one maximal voluntary contraction, one contraction at the 60% of the actual maximal force and at the 80% of the actual maximal force. During each contraction, transcranial magnetic stimulation over the motor cortex will be delivered to assess corticospinal voluntary activation (central fatigue). Single-twitch electrical stimulations will be delivered on the femoral nerve during the maximal voluntary contraction and at rest to evaluate peripheral fatigue. The isokinetic BW-QIF test blocks consist in 100 contractions at 120° deg.s-1 and 60° of range of motion (0.5-s contraction /0.5-s rest).

DIAGNOSTIC_TEST

Cycloergometer body weight-based quadriceps intermittent fatigue test (BW-QIF Test)

The BW-QIF test is an interval incremental contraction test including blocks of discontinuous 100-s effort. Neuromuscular evaluation of the knee extensors between blocks (duration 25 s) includes one maximal voluntary contraction, one contraction at the 60% of the actual maximal force and at the 80% of the actual maximal force. During each contraction, transcranial magnetic stimulation over the motor cortex will be delivered to assess corticospinal voluntary activation (central fatigue). Single-twitch electrical stimulations will be delivered on the femoral nerve during the maximal voluntary contraction and at rest to evaluate peripheral fatigue. The BW-QIF test blocks on the cycloergometer consist in 100 s of cycling at 60 Revolution Per Minute (RPM).

DIAGNOSTIC_TEST

Isometric BW-QIF Test (Body weight-based quadriceps intermittent fatigue test)

The BW-QIF test is an interval incremental contraction test including blocks of discontinuous 100-s effort. Neuromuscular evaluation of the knee extensors between blocks (duration 25 s) includes one maximal voluntary contraction, one contraction at the 60% of the actual maximal force and at the 80% of the actual maximal force. During each contraction, transcranial magnetic stimulation over the motor cortex will be delivered to assess corticospinal voluntary activation (central fatigue). Single-twitch electrical stimulations will be delivered on the femoral nerve during the maximal voluntary contraction and at rest to evaluate peripheral fatigue. The isometric BW-QIF test blocks consist in 10 contractions (5-s contraction / 5-s rest).

Sponsors & Collaborators

• Centre Hospitalier Universitaire de Saint Etienne

  lead OTHER

Principal Investigators

• Léonard FEASSON, MD PhD · CHU SAINT-ETIENNE

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2021-04-13

Primary Completion

2022-05-09

Completion

2022-06-03

Countries

• France

Study Locations