Abstract
Introduction: Strength training is often included in the training program of cyclists as it has been shown to increase performance. Some cyclists and coaches utilize a certain type of interval training where cycling cadence is held lower than normal to elicit higher muscular force production for a given power output. Such training has been used with the intent to develop muscular strength, although very limited data to support this notion exists. Whether low-cadence interval training at typically prescribed moderate intensities provides a similar stimulus for strength development to that of heavy weight training is unknown. Purpose: This investigation was conducted to examine the decrement in maximal force production following either low-cadence interval training or heavy strength training to determine if neuromuscular fatigue induced by each training type is similar among trained cyclists. Methods: Eighteen trained male cyclists completed a graded exercise test to determine VO2max and the power output corresponding to the respiratory compensation point (RCP). Latin Square counterbalanced design was used to organize subsequent lab visits where subjects performed one the following: a low cadence cycling bout at typical prescription [5 x 4 min, 40 rpm, power @ RCP], a control cycling bout with the same intensity of intervals at 90 rpm, and a leg press strength training exercise consisting of 4 sets at 80% of estimated 1RM. Force production was estimated for each activity, and the mean % MVIC for each activity was calculated. MVIC measurements were taken before and after exercise to evaluate the strength loss induced by each training type. A two-way repeated measures ANOVA with pairwise mean comparisons was used to determine if significant differences existed fatigue across time and training type. Results: The individual relative leg strength (leg press 1RM/ body weight) of cyclists (7.6) was significantly higher than the 90th percentile for ACSM normative data (2.1). Average loading per repetition during WT (102.8 kg) was significantly higher than LC (39.4 kg). Each repetition was performed at 80% of 1RM for WT, and 20.6% MVIC for LC. Decline in maximal force following WT (9.2%) was significantly greater than LC (2.1%), but not NC (5.7%). Individual strength and VT%VO2max were significantly correlated with fatigue. Greater strength was associated with less fatigue following LC (r = -0.56), and greater VT%VO2max was associated with less fatigue following WT (r = 0.65). Conclusion: The training stimulus induced by typically prescribed low-cadence interval training is not similar to traditional weight training. Based on the difference in the decline in force production between them, it is not likely that LC drives strength development to a similar degree as WT. It is possible that increased training intensity during LC could lead to greater acute strength loss, but this remains to be determined.