Four Weeks of Muscular Endurance Resistance Training Does Not Alter Fatigue Index

Background of Study: The implementation of a muscular endurance resistance training (MERT) program has been shown to be beneficial in augmenting the onset of blood lactate accumulation (OBLA). However, the effects of MERT on local muscular endurance has not been investigated. Objectives: The purposes of the current study were to investigate the effects of 4 weeks of MERT on local muscular endurance, and the relationship between OBLA and fatigue index (FI). Methods: Endurance trained males were randomly designated to either the experimental (EX) or control (CON) group: 9 EX and 8 CON. All participants continued current aerobic training. Baseline measures included OBLA, 1 repetition maximum (1RM) for: leg press (LP), leg curl (LC), and leg extension (LE). FI of the quadriceps was assessed via a dynamometer and the Thorstesson protocol. In addition, the EX group performed supervised MERT training for four weeks. A two way ANOVA was used to assess group and time differences in performance measures. The relationship between OBLA and FI was assessed using Pearson’s Correlation. Results: No significant group differences were observed in all baseline measurements (p>0.05). There were no significant group or time differences for OBLA and FI (p>0.05). Pearson’s correlation revealed no significant relationship (p>0.05, r=<0.01) existed between FI and OBLA. Conclusions: It was observed that four weeks of MERT provided an insufficient stimulus to improve OBLA and FI, and no significant relationship existed between OBLA and FI. Athletes using MERT should include additional mesocycles for favorable adaptations to local muscular endurance and OBLA.

Four weeks of muscular endurance resistance training did not improve fatigue index or onset of blood lactate accumulation.