Eccentric cycling exercise can be a promising modality fwith lower respiratory demands and higher power output. Assistive devices like neuromuscular electrical stimulation (NMES) and compressive garment (CG) accelerates muscle pumping and relieve the eccentric exercise-induced muscle soreness.

Phenotypes and mitochondrial metabolism are crucial to regulate acquired immnunity of T lymphocytes. The study aimed to investigate the effects of eccentric cycling exercise training combined with NMES and CG on mitochondrial phenotypes and bioenergetics in T lymphocytes in sedentary males. The hypothesis were an acute/intense exercise decreased the mitochondrial respiratory capacities of OXPHOS, ETS and bioenergetics, while eccentric cycling training could elevate the diminished mitochondrial functions.

Methods: Twelve sedentary healthy males were randomly assigned to either eccentric cycling with assistive devices (ECA, n=10) or eccentric cycling only (ECC, n=10). All participants performed ECA or ECC at an intensity of 60% to 120% maximal workload progressively on a costumed bicycle ergometer for 40 min/day, 5 days/week for 5 weeks. ECA performed NMES for 20min/session after cycling, while ECC was seated for resting 20 min. Systemic aerobic fitness, phenotypes of T lymphocytes, mitochondrial OXPHOS, ETS respiratory capacities, and bioenergetics in T lymphocytes were analyzed.

Inclusion Criteria:

• Sedentary lifestyle (exercise<20min/session; <1session/week for a year or longer).
• Nonsmokers, nonusers of medications/vitamins.
• No any cardiopulmonary, neuromuscular, and hematological risks.

Exclusion Criteria:

• Have regular exercise habits (i.e., exercise frequency once per week, duration >20 min).
• Have retabolic or musculoskeletal disease.

Due to the blood experiments, we recruited male participants only to avoid interference of menstrual cycle.