This single-center, single-blind, three-arm randomized controlled trial aims to compare the effects of weekend-concentrated exercise, regularly distributed exercise, and usual lifestyle on aerobic capacity and skeletal muscle strength in sedentary female university students. Sixty participants aged 18 to 25 years will be randomly assigned in a 1:1:1 ratio to a weekend warrior group, a regular exercise group, or a control group.

The intervention will last 8 weeks. Both exercise groups will complete 150 minutes of moderate-intensity exercise per week, combining resistance exercise and jogging, but the exercise sessions will be distributed differently across the week. The control group will maintain its usual lifestyle without receiving the prescribed exercise intervention.

The primary outcomes are peak oxygen uptake and isokinetic peak torque. Secondary outcomes include body composition, maximal heart rate, maximal power and time to exhaustion, 12-minute run performance, isokinetic mean torque, physical activity, sleep quality, exercise self-efficacy, emotional status, cognitive function, adherence, feasibility, and exercise-related adverse events.

Sedentary behavior and insufficient physical activity are common among university students. Although adults are generally encouraged to accumulate at least 150 minutes of moderate-intensity physical activity per week, academic demands and limited weekday availability may make regularly distributed exercise difficult to maintain. The weekend warrior exercise pattern concentrates most of the recommended weekly exercise volume into one or two days and may therefore provide a more flexible exercise strategy.

Eligible participants will be female university students aged 18 to 25 years who report sitting for at least 6 hours per day and whose physical activity status is further assessed using the International Physical Activity Questionnaire. After health screening, written informed consent, and baseline assessments, participants will be randomly allocated in a 1:1:1 ratio to one of three parallel groups.

Participants in the weekend warrior group will exercise on two consecutive days per week. On each exercise day, they will complete 30 minutes of resistance exercise and 45 minutes of jogging, for a total of 75 minutes per day and 150 minutes per week.

Participants in the regular exercise group will exercise on three days per week. Each session will include 20 minutes of resistance exercise and 30 minutes of jogging, for a total of 50 minutes per session and 150 minutes per week.

The resistance exercise content, jogging format, intensity-control principles, and safety requirements will be comparable between the two exercise groups. Jogging intensity will generally be maintained at approximately 60% to 75% of maximal heart rate or a rating of perceived exertion of 12 to 14. Resistance exercise will target the lower limbs, core, and other major muscle groups and may include squats, lunges, glute bridges, calf raises, and planks.

Participants in the control group will maintain their usual study and lifestyle habits and will not receive the exercise intervention prescribed by the study. Their participation in any additional structured exercise will be monitored during the study.

Assessments will be conducted before and after the 8-week intervention. The primary outcomes will be peak oxygen uptake and isokinetic peak torque. Secondary outcomes will include body composition, maximal heart rate, maximal power and time to exhaustion, 12-minute run performance, isokinetic mean torque, physical activity, sleep quality, exercise self-efficacy, emotional status, cognitive function, adherence, and feasibility. Exercise completion, perceived exertion, discomfort, adverse reactions, and exercise-related events will be recorded throughout the intervention.

Inclusion Criteria:

• Female university students aged 18 to 25 years.
• Self-reported sedentary time of at least 6 hours per day, further assessed using the International Physical Activity Questionnaire (IPAQ).
• No cardiovascular, pulmonary, neurological, metabolic, or musculoskeletal diseases.
• Relatively regular menstrual cycles.
• Able to understand the study procedures, willing to complete the intervention and assessments, and willing to provide written informed consent.

Exclusion Criteria:

• Any condition identified through clinical assessment or health screening that makes participation in moderate-intensity exercise or exercise-to-exhaustion testing inappropriate.
• Participation in regular exercise training, a systematic weight-loss or body-shaping program, or another exercise intervention study within the previous 3 months.
• Recent substantial body-weight fluctuations that may affect body-composition assessment.
• Cardiovascular, pulmonary, neurological, metabolic, or musculoskeletal diseases, or current use of medications that may affect exercise performance, heart-rate responses, or muscle function.
• Irregular menstrual cycles.
• Inability to complete the 8-week intervention, post-intervention assessments, or required study records.

Individual participant data will not be shared. Study findings will be reported only in aggregate or anonymized form in academic publications, conference presentations, and research reports, in accordance with the approved protocol and informed consent.

Due to the nature of the exercise interventions, participants and exercise supervisors cannot be blinded. Outcome assessors and data analysts will be blinded to group allocation.