Moderate Load Eccentric Exercise; A Distinct Novel Training Modality

Abstract

Over the last 20 years a number of studies have been published using progressive eccentric exercise protocols on motorized ergometers or similar devices that allow for controlled application of eccentric loads. Exercise protocols ramp eccentric loads over an initial 3 weeks period in order to prevent muscle damage and delayed onset muscle soreness. Final training loads reach 400–500 W in rehabilitative settings and over 1200 W in elite athletes. Training is typically carried out three times per week for durations of 20–30 min. This type of training has been characterizes as moderate load eccentric exercise. It has also been denoted RENEW (Resistance Exercise via Negative Eccentric Work by LaStayo et al., 2014). It is distinct from plyometric exercises (i.e., drop jumps) that impose muscle loads of several thousand Watts on muscles and tendons. It is also distinct from eccentric overload training whereby loads in a conventional strength training setting are increased in the eccentric phase of the movement to match concentric loads. Moderate load eccentric exercise (or RENEW) has been shown to be similarly effective as conventional strength training in increasing muscle strength and muscle volume. However, as carried out at higher angular velocities of joint movement, it reduces joint loads. A hallmark of moderate load eccentric exercise is the fact that the energy requirements are typically 4-fold smaller than in concentric exercise of the same load. This makes moderate load eccentric exercise training the tool of choice in medical conditions with limitations in muscle energy supply. The use and effectiveness of moderate load eccentric exercise has been demonstrated mostly in small scale studies for cardiorespiratory conditions, sarcopenia of old age, cancer, diabetes type 2, and neurological conditions. It has also been used effectively in the prevention and rehabilitation of injuries of the locomotor system in particular the rehabilitation after anterior cruciate ligament surgery.

Superior Effects of Eccentric to Concentric Knee Extensor Resistance Training on Physical Fitness, Insulin Sensitivity and Lipid Profiles of Elderly Men

“…Thus, the greater increases in muscle function for eccentric training group than concentric training group were most likely due to the eccentric contractions performed by eccentric training group. This suggests that eccentric training is more effective than concentric training to attenuate sarcopenia and dynapenia, which supports the statement of Hoppeler (2016) in his recent review paper that eccentric exercise training is effective for prevention and reduction of sarcopenia.…”

Skeletal Muscle Remodeling in Response to Eccentric vs. Concentric Loading: Morphological, Molecular, and Metabolic Adaptations

“…Thus, eccentric contractions have been advocated as particularly suitable for recovering muscle mass and strength in elderly and clinical populations (Hoppeler, 2014; Mitchell et al, 2017). The features of metabolic and energetic costs of ECC compared to CON contractions have been recently reviewed by Professor Hoppeler (Hoppeler, 2016). …”

Eccentric cycling is more efficient in reducing fat mass than concentric cycling in adolescents with obesity

“…Three types of ECC training can be distinguished: (a) plyometric exercises (such as drop jumps, with contractions lasting milliseconds and producing thousands of watts of negative power), (b) classical ECC resistance exercises (protocols consisting of near maximal ECC contractions lasting few seconds, used to lift and lower weights), (c) “continuous moderate load ECC exercises” (also denoted as resistance exercise via negative eccentric work 5 ). Thus, alternative training modalities, such as cycling with special motorized ECC cycle ergometers, downhill walking or running, and stepping exercises, have been characterized as “continuous moderate load ECC exercise” . One of the physiological characteristics of ECC cycling is that it lowers metabolic demand, compared with CON cycling when performed at the same mechanical power , due to the combination of a high muscle force with low energy cost (ie , low oxygen uptake ratio and /power).…”