Frailty and sarcopenia are modifiable risk factors for morbidity and mortality in patients with ESRD. Exercise is the recommended intervention to prevent frailty and sarcopenia, however, many clinical trials have shown limited clinical improvement in muscle mass and physical function. We propose that mitochondrial dysfunction is one of the deterrents to the effectiveness of the exercise. We plan to evaluate the additive effect of HIIT and CoQ10, a mitochondrial-targeted therapy, on mitochondrial function and physical performance. Understanding the interplay among CoQ10, exercise, and mitochondrial function will identify novel mechanisms to improve the efficiency of exercise. This will also serve to prevent frailty, sarcopenia, and muscle dysfunction in patients with ESRD.