Effects of Home-Based Eccentric Training at Long Muscle Length on Functional Capacity and Neuromechanical Function in Healthy Older Adults
试验速览
- 阶段
- 不适用
- 状态
- Enrolling By Invitation
- 发起方
- 入组人数
- 30
- 试验地点
- 1
- 主要终点
- 5 times Sit to Stand
研究概览
简要总结
As aging leads to a decline in muscle function and overall physical performance, interventions targeting muscle strength and neuromechanical properties are critical for maintaining functional independence in older adults. Long-length eccentric training has shown promise in enhancing muscle performance, but its effects in older adults, particularly in a home-based setting, remain underexplored.
The aim of this trial is to assess whether a targeted home-based training intervention incorporating long-length eccentric contractions can enhance functional capacity and neuromechanical properties in healthy older adults. Participants will be semi-randomly allocated to one of two groups: an experimental group incorporating long-length eccentric contractions (Group 1) or a conventional resistance training group (Group 2), with group assignment stratified to ensure an equal number of men and women in each group. Each participant will complete three laboratory-based experimental sessions (i.e., two Pre-training sessions and one Post-training session) , during which five key evaluations will be conducted: (i) the 5-Time Sit to Stand test, serving as the primary outcome measure; (ii) the Timed Up and Go test; (iii) assessments of isometric and dynamic muscle strength in the knee extensors and plantar flexors; (iv) measurements of the cross-sectional areas of the vastus lateralis, rectus femoris, gastrocnemius medialis, and soleus muscles; and (v) evaluation of tendon stiffness.
Following the pre-evaluation, each participant will engage in a 24-session, semi-supervised, home-based training protocol over a period of 8 to 11 weeks. The training program will include eight exercises, with four targeting the upper limbs and four focused on the lower limbs. Group 1 will perform the lower limb exercises at long muscle lengths, while Group 2 will perform the same exercises in a conventional manner (i.e., at neutral or shorter muscle lengths). The total training volume (calculated as repetitions × sets, in arbitrary units) will be matched across both groups, ensuring that any observed differences in outcomes are attributable to the specific training modality rather than differences in workload.
详细描述
Home-based resistance training has emerged as a practical alternative for individuals who lack access to traditional, facility-based exercise programs. This is particularly relevant for older adults, who often face multiple barriers to participating in supervised center-based training-the current gold standard-including reduced mobility, transportation difficulties, and financial constraints. As a result, home-based programs can offer a more accessible option to support engagement in resistance training. Evidence suggests that home-based resistance training can lead to improvements in strength and functional capacity among healthy older individuals; however, these gains tend to be modest. One key limitation is that exercise intensity in home settings may not progress adequately over time, often due to the absence of supervision or limited motivation to increase effort.
Besides training localization and level of supervision, the modality of contraction appears to be of importance. Previous evidences in young but also elderly adults suggest that eccentric training should be performed at long muscle length to obtain the greatest improvements in neuromuscular and physical functions. At the muscle level, the force-length relationship indicates that muscle tension is greater at long vs short muscle length. This is an obvious but important point since mechanical tension during training exercises is a key parameter for muscle plasticity and strength gains. It has been reported positive effects of a short-term (i.e. 3-week) eccentric training performed in a lengthened position on architectural and functional characteristics of the hamstrings in young adults. However, they found no difference between long and short muscle lengths, likely because of the short training duration. It has also been reported significant neuromuscular (e.g. fascicle length, pennation angle, voluntary activation level) and functional (e.g. muscle force) improvements after a 6-week eccentric training at long muscle length in the hamstrings of young adults. Resistance training interventions focusing on eccentric contractions seem particularly interesting for older individuals, as they are less metabolically demanding than concentric contractions for comparable workloads.
Although home-based resistance training programs emphasizing eccentric contractions have been shown to be more effective than those focusing on concentric contractions for improving lower limb strength, mobility, and postural stability in healthy older adults, the integration of eccentric exercises performed at long muscle lengths within home-based protocols has yet to be explored. This represents a significant challenge, as both contraction intensity and muscle length are difficult to monitor and control in real-world, home-based settings compared to tightly controlled laboratory environments.
The aim of this trial is to assess whether a home-based resistance training program incorporating long-length eccentric contractions of the lower limbs can lead to greater improvements in functional capacities and neuromechanical properties in healthy older adults compared to a conventional resistance training program. Participants will be randomly assigned to one of two groups: (i) a control group performing a conventional home-based resistance training program, (ii) an experimental group following the same program, with the addition of specific long-length eccentric contractions integrated into lower limb exercises.
This trial is designed to address two primary research questions:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 60 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Men or women 60 years and older
- •Individuals eligible for social security coverage
- •Individuals without health issues (e.g., musculoskeletal injuries, chronic conditions)
- •Individuals who have given their informed consent
排除标准
- •Accustomed to resistance exercise (i.e., no participation in a resistance training program within the 6 months prior to enrollment, or not engaging in lower-limb resistance training more than once per week as part of their current routine).
- •Pathologies affecting muscle strength in the lower limbs (e.g., neurological or neuromuscular conditions, history of ankle or knee trauma)
- •Individuals residing in a healthcare or social institution
- •Individuals receiving psychiatric care
- •Individuals deprived of their liberty
- •Adults under legal protection (guardianship, curatorship, or legal safeguard)
- •Participation in another ongoing biomedical research study
- •Individuals in an emergency situation
- •Individuals not covered by social security
- •BMI over 30
- •Minimal Mental State Examination (MMSE) score of 25 or lower
- •Significant visual impairment
研究组 & 干预措施
Long muscle length eccentric training program
Participants assigned to this arm will complete a home-based training program consisting of 24 sessions, including 20 sessions performed independently at home and 4 sessions conducted in small groups at the laboratory. The laboratory-based sessions will be scheduled in coordination with each participant to ensure regular spacing-approximately one supervised session every five home-based sessions-while accommodating individual availability. Group sizes will be maintained between 2 and 5 participants per session to foster motivation and promote adherence.
The training program will include conventional resistance exercises, with progressive increases in intensity and volume tailored to each participant's capabilities. In this intervention group, four specific exercises targeting the knee extensors and plantar flexors will be performed at long muscle lengths, distinguishing it from Group #2, where these exercises will be performed in a conventional manner (i.e., at neutral or shorter mus
干预措施: Home-based eccentric training at long muscle length (Other)
Conventional training program
Participants in this arm will follow a home-based resistance training program consisting of 24 sessions, including 20 sessions performed independently at home and 4 sessions conducted in small groups at the laboratory, as previously described. The training will involve conventional resistance exercises, with progressive adjustments in intensity and volume based on each participant's physical capacity and progression.
Note: the total training volume (i.e., number of repetitions × number of sets, in arbitrary units) will be matched between groups, ensuring that any differences in outcomes can be attributed to the specific training modality rather than differences in workload.
干预措施: Conventional home-based training (Other)
结局指标
主要结局
5 times Sit to Stand
时间窗: At baseline (i.e., prior to the start of training) and at study completion (i.e., within one week following the final training session
The subjects will complete five times STS repetitions on a standardized armless chair. After the cue "ready, set, go!", the subjects will start performing STS repetitions as rapidly as possible from the sitting position with their buttocks touching the chair to the full standing position, with their arms crossed over the chest. Verbal encouragement will be given during the test. The STS test will finish when the subjects sit on the chair after the fifth STS repetition, and the time needed to complete the task will be recorded with a stopwatch to the nearest 0.01 s.
次要结局
- Isometric and dynamic muscle strength(At baseline (i.e., prior to the start of training) and at study completion (i.e., within one week following the final training session)
- Timed Up and Go Test(At baseline (i.e., prior to the start of training) and at study completion (i.e., within one week following the final training session)
- Cross sectional areas of vastus lateralis (VL), rectus femoris (RF), soleus (SOL) and gastrocnemius medialis (GM) muscles.(At baseline (i.e., prior to the start of training) and at study completion (i.e., within one week following the final training session)
- Stiffness of VL and Achilles tendons(At baseline (i.e., prior to the start of training) and at study completion (i.e., within one week following the final training session)
- Training metrics(Participants will complete the questions after each training session, resulting in 24 recordings.)
研究者
Robin Souron
Associate professor
Institut Pasteur de Lille