Long-Distance Running

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.

Statins lower low-density lipoprotein cholesterol (LDL-C) and help prevent atherosclerotic cardiovascular disease, but some users develop statin-associated muscle symptoms (SAMS) such as soreness, stiffness, weakness, or elevated creatine kinase (CK). These symptoms may be more noticeable during exercise. Regular long-distance running improves cardiopulmonary fitness-VO₂max, aerobic threshold (AT), and respiratory compensation point (RCP)-mainly through mitochondrial and metabolic adaptations. Prior studies suggest that lipophilic statins like simvastatin may blunt these adaptations, while hydrophilic statins such as rosuvastatin may have a smaller impact. However, prospective data in habitual endurance runners are limited. This randomized controlled trial will examine how rosuvastatin affects cardiopulmonary fitness improvements and muscle tolerance in individuals who run at least three times per week and meet clinical criteria for statin therapy. After informed consent and baseline cardiopulmonary exercise testing (CPET), participants will be randomized to rosuvastatin 10 mg daily or no statin therapy for three months. Both groups will maintain their usual training routines, and training load will be recorded using heart-rate-based TRIMP. CPET will be repeated monthly to assess changes in VO₂max, AT, and RCP, and muscle enzymes and SAMS will be evaluated at each visit. The study aims to clarify whether rosuvastatin influences endurance-related physiological adaptations or increases muscle symptoms in regular long-distance runners.