Effect of different inter-repetition rest intervals across four load intensities on velocity loss and blood lactate concentration during full squat exercise. Issue 24 (17th December 2018)

• Record Type: Journal Article
• Authors: Mora-Custodio, Ricardo; Rodríguez-Rosell, David; Yáñez-García, Juan Manuel; Sánchez-Moreno, Miguel; Pareja-Blanco, Fernando; González-Badillo, Juan José
• Is Part Of: Journal of sports sciences. Volume 36:Issue 24(2018)
• Page Start: 2856
• Page End: 2864
• Publication Date: 2018-12-17
• Subjects: Resistance training -- fatigue -- metabolic stress -- cluster configurations; Sports -- Periodicals; Sports -- Physiological aspects -- Periodicals; Sports -- Psychological aspects -- Periodicals; 612.044
• DOI: 10.1080/02640414.2018.1480052
• Languages: English
• ISSNs: 0264-0414

Abstract

ABSTRACT: This study aimed to analyze the acute effect of inter-repetition rest (IRR) intervals on mechanical and metabolic response during four resistance exercise protocols (REPs). Thirty resistance-trained men were randomly assigned to: continuous repetitions (CR), 10 s (IRR10) or 20 s (IRR20) inter-repetition rest. The REPs consisted of 3 sets of 6, 5, 4 and 3 repetitions against 60, 70, 75 and 80% 1RM, respectively, in the full squat exercise. Muscle fatigue was assessed using: percentage of velocity loss over three sets, percentage of velocity loss against the ~1 m·s −1 load (V1 m·s −1 ), and loss of countermovement jump (CMJ) height pre-post exercise. Blood lactate was measured before and after exercise. The percentage of velocity loss over three sets and lactate concentration were significantly lower ( P < 0.05) for IRR groups compared to CR in all REPs. The CR group showed a significantly higher ( P < 0.05) velocity loss against V1 m·s −1 load and loss of CMJ height pre-post exercise than IRR groups in REP against 60% 1RM. In conclusion, both IRR groups produced a significant lower degree of fatigue compared to CR group. However, no significant differences were found in any measured variables between IRR configurations.