The Accumulative Effect of Concentric‐Biased and Eccentric‐ Biased Exercise on Cardiorespiratory and Metabolic Responses to Subsequent Low‐Intensity Exercise: A Preliminary Study

Abstract

The study investigated the accumulative effect of concentric-biased and eccentric-biased exercise on cardiorespiratory, metabolic and neuromuscular responses to low-intensity exercise performed hours later. Fourteen young men cycled at low-intensity (~60 rpm at 50% maximal oxygen uptake) for 10 min before, and 12 h after: concentric-biased, single-leg cycling exercise (CON) (performed ~19:30 h) and eccentric-biased, double-leg knee extension exercise (ECC) (~06:30 h the following morning). Respiratory measures were sampled breath-by-breath, with oxidation values derived from stoichiometry equations. Knee extensor neuromuscular function was assessed before and after CON and ECC. Cardiorespiratory responses during low-intensity cycling were unchanged by accumulative CON and ECC. The RER was lower during low-intensity exercise 12 h after CON and ECC (0.88 ± 0.08), when compared to baseline (0.92 ± 0.09; p = 0.02). Fat oxidation increased from baseline (0.24 ± 0.2 g·min−1) to 12 h after CON and ECC (0.39 ± 0.2 g·min−1; p = 0.01). Carbohydrate oxidation decreased from baseline (1.59 ± 0.4 g·min−1) to 12 h after CON and ECC (1.36 ± 0.4 g·min−1; p = 0.03). These were accompanied by knee extensor force loss (right leg: −11.6%, p < 0.001; left leg: −10.6%, p = 0.02) and muscle soreness (right leg: 2.5 ± 0.9, p < 0.0001; left leg: 2.3 ± 1.2, p < 0.01). Subsequent concentric-biased and eccentric-biased exercise led to increased fat oxidation and decreased carbohydrate oxidation, without impairing cardiorespiration, during low-intensity cycling. An accumulation of fatiguing and damaging exercise increases fat utilisation during low intensity exercise performed as little as 12 h later.

Acute Cardiorespiratory and Metabolic Responses to Incremental Cycling Exercise in Endurance- and Strength-Trained Athletes

“…However, there was a significant between-group difference in resting RER which is hard to explain and might be caused by the greater pre-exercise stress in individuals from STR and CON groups. In a few previous studies, comparable results in trained, lowtrained, and untrained individuals have been found [46,47]. Similar to HR response, peak RER values ≥ 1.0 AU (in CON group) and ~1.0 AU (STR group) also indirectly suggest that the final stage of cycling exercise was mainly performed in anaerobic conditions.…”

Eccentric Training Improves Body Composition by Inducing Mechanical and Metabolic Adaptations: A Promising Approach for Overweight and Obese Individuals

“…With regard to glucose metabolism and insulin resistance, ECC training similarly offers benefits to patients with metabolic risk factors (Drexel et al, 2008 ; Marcus et al, 2008 ; Miles et al, 2016 ). Thus, decreased insulin resistance, intra-myocellular lipid pool changes, and decreases in glucose oxidation after ECC exercises support the growing interest for the ECC modality for the management of metabolic diseases (Hughes et al, 2010 ; Beaven et al, 2014 ; Gavin et al, 2015 ). Notably, ECC exercise may protect against low-grade inflammation usually observed in patients with obesity (Nascimento et al, 2016 ).…”