For older adults, resistance training is a widely recognized strategy to maintain or improve muscle strength and function which consequently leads to an improved quality of life. Without it, our ability to perform physical tasks becomes difficult as we age. The role of muscle strength (the ability for the muscles to generate maximal force) has been proven by numerous studies to be of upmost importance in optimising long-term function in older adults, where decreased strength results in a reduction in functional performance.
Although the aging process is inevitable even for master athletes, the rate of functional decline can be reduced and even somewhat reversed through exercise training. Whilst traditional resistance training provides a plethora of musculoskeletal and neuromuscular benefits, one form of resistance training that has been gaining popularity due to its lower metabolic demands and its effectiveness- is eccentric based training.
What is an Eccentric-Based Exercise?
Eccentric based exercise involves focusing on the lengthening phase of a muscle contraction, rather than the emphasised concentric phase. For the older individual, a step down is a perfect example of this, where the individual must lower one leg off the step, in a slow and controlled manner (think 2-3 seconds on the descent) which will elicit the desired eccentric contraction. This allows for the quadriceps and gluteal muscles to lengthen under tension. Emphasising the lowering phase of a movement, under load, places greater mechanical stress on the muscle fibres, which as a result results in remarkable adaptations to the tissues involved. To make an eccentric exercise more difficult, you can increase the time of the descent, complete more repetitions, or add weight. This strategy can be used for a variety of different exercises (e.g. a bicep curl, bench press, leg extensions or curls), depending on what muscles you want to target.
Why should I complete eccentric based exercises?
The current literature provides strong evidence for the benefits of eccentric- based exercise. Studies completed by Roig et al (2018) and Cretknik et al (2022) have found that eccentric based exercise is often superior to, or at least as good as, concentric training- particularly for preserving health and function in older adults. Eccentric contractions lead to greater recruitment of muscle fibres and increased activations of motor units, contributing to enhanced strength development. Furthermore, a meta-analysis by Franchi et al (2020) found that eccentric training was particularly effective in promoting hypertrophy, indicating its potential as a valuable tool for muscle growth.
Not only is it an effective tool for muscle growth and strength, but this type of exercise also plays a role in injury prevention and rehabilitation. For example, for soft tissue acute and chronic injuries such as tendinopathy, eccentric exercises can effectively reduce pain and improve function, as this targets the tendons by generating tensile forces, which then can stimulate collagen synthesis and remodelling.
Eccentric exercise for longevity:
Whilst eccentric type training is important for muscle growth, injury rehab and prevention, it is also an integral tool for maintaining longevity in older adults. For older individuals, daily activities such as walking, sitting, standing, stair climbing and descending require high physical demands. Furthermore, older adults struggle with tasks that require more neuromuscular control, such as sitting down or going downstairs (which are eccentrically based activities) and because of this, this can lead to falls and injuries. However, completing exercise programs that focus on stair ascending and descending have shown to significantly improve performance in these areas. The reason for this is that as we build more eccentric strength, neuromuscular adaptations such as neuromuscular control and sensory integration take place- in other words we learn how to better apply the brakes. These improvements significantly reduce falls risk, improves functional fitness, and counteracts the effects of sarcopenia- thus improving quality of life. By completing eccentric based exercises, this can target stabilising muscles and joints in ways that traditional resistance training might not. Furthermore, some studies reported lower or minimal cardiorespiratory load evoked by eccentric exercise, which could be an advantage when applied for older individuals.
To learn more about this type of exercise training, it is recommended to see Accredited Exercise Physiologist or Scientist, who can provide advise and prescribe appropriate exercises that tailor to your needs.
