Comparison Between High‐Intensity and High‐Volume Resistance Training on the Acute Myokine Response in Resistance Trained Men

Abstract

Secreted protein acidic and rich in cysteine (SPARC) and musclin are myokines implicated in glucose uptake signaling. SPARC has been shown to increase expression of GLUT4 on myocytes, while musclin has been shown to inhibit insulin signaling, suggesting a possible increased reliance on fat metabolism during exercise. SPARC and musclin concentrations have been shown to increase in response to acute exercise. However, the effect of different resistance training paradigms on changes in the plasma concentrations of these myokines remain unknown. The purpose of this study was to examine the acute response of these myokines following two commonly utilized resistance training paradigms. Twenty resistance trained men volunteered to participate in this study. Following a two‐week preparatory period, participants were randomly assigned to either a high‐intensity (HI; n=10, 22.6±2.3 y; 87.0±15.1 kg; 1.79±0.05m) or high‐volume (HV; n=10, 24.5±2.6 y; 89.5±12.9 kg; 1.66±0.34m) group. Prior to the first training session, participants completed an acute lower‐body exercise protocol. The HI protocol consisted of four sets of 3–5 reps at 90% 1RM, while the HV protocol consisted of four sets of 10–12 reps; 70% 1RM. Blood samples were collected at baseline (BL), immediately post (IP), 30 minutes' post (30P), and 60 minutes' post (60P) exercise during the acute exercise protocol. Following the acute exercise protocol, participants then completed 7 weeks of training under their respective exercise paradigms. The acute exercise protocol was repeated following the training intervention. Data was analyzed using a 2×2×4 (group [HI vs. HV] × training [pre vs. post] × time [BL‐60P]) repeated measures ANOVA. No significant group × time × training, group × time, or group × training interactions were observed for SPARC (p>0.05). However, a significant training × time interaction was observed (p=0.016). With both groups combined, circulating concentrations of SPARC were significantly lower at 60P post‐training compared to pre‐training (p=0.001; mean diff: −29.5 ± 30.9 ng/mL). Further, a trend was observed towards a post‐training decrease in SPARC at 30P (p=0.089; mean diff: −11.3 ± 27.4 ng/mL). No significant group × time × training, group × time, group × training, or training × time interactions were observed for musclin. However, a significant main effect for training was observed (p=0.031) indicating an attenuation of the musclin response post‐training compared to pre‐training. A significant main effect for time was also observed for musclin (p=0.007). Post‐hoc analysis revealed that musclin concentrations were significantly lower at 60P compared to BL (20.9 ± 75.3 ng/mL), irrespective of group or training. Results of this study indicated that the temporal SPARC response to resistance exercise is attenuated following 7‐weeks of resistance training, with no differences between HI and HV training. A decline in musclin concentrations was observed at 60P relative to BL, irrespective of group or training. Further, musclin concentrations were lower post‐training compared to pre‐training.