Immediate, Residual, and Cumulative Effects of Fartlek, Hill Circuit, and Roll-On Training in Long-Distance Runners

This randomized controlled trial will compare Fartlek, hill circuit, and roll-on training in well-trained long-distance runners. Twenty-one eligible runners will be randomly assigned to one of three training groups and will complete a 12-week intervention comprising 24 prescribed training sessions. The study will evaluate immediate responses to conditioning, 24-hour recovery responses, and cumulative changes in running performance, aerobic fitness, and training-related responses. Outcomes will include heart rate, blood lactate concentration, rating of perceived exertion, delayed-onset muscle soreness, recovery and wellness indicators, internal training load, 5-km time-trial performance, and VO₂max. The findings will provide evidence regarding the comparative responses to these three conditioning modalities in well-trained long-distance runners.