The purpose of this study is to understand how college students' biomarkers change with a relatively short bout of moderate-intensity physical activity. The investigators are comparing biomarkers in between self-reported physically active and sedentary students in terms of their percent difference and change. The investigators are also studying physically active versus sedentary college students' mental health. This is a mentored student research project in the investigator's lab (not part of a thesis, dissertation, or other coursework requirements), where multiple students have developed research questions using the same study design.

This study will use a two-group (sedentary versus active) pre-test, post-test study design. Following the informed consent process, participants will complete the pre-test data collection protocol including the first venipuncture blood draw for ammonia, insulin, cortisol, and c-reactive protein, first finger stick blood sample for glucose measurement, reporting of food eaten for the day as well as transportation methods to the study site. Resting heart rate will be measured.

Following a 15-minute waiting period to minimize potential effects from the blood draw, participants will walk with a study team member to a reserved elliptical machine. For the exercise component, the lab member will emphasize to the participant about maintaining the desired heart rate for moderate intensity exercise. The participant will use the elliptical for 12 minutes, without music, conversation, or general entertainment. Appropriate warm-up and cool-down is added in to the exercise time (the first two minutes and last two minutes) with preference of moderate intensity exercise lasting 8 minutes.

Participants will then walk with the study team member back to the Lab for post-test data collection. Post-test data collection follows the same procedures as pre-test data collection. Participants also will take a mental health questionnaire.

Inclusion Criteria:

• This study will enroll full-time students at the investigator's university who are aged 18-34 years.
• Participants will be generally healthy participants, assessed using the 2020 Physical Activity Readiness Questionnaire (first 7 questions) as a screening tool. Individuals who answer "no" to all of the 7 questions will be deemed healthy enough to take part.
• Two balanced groups will be created based on self-reported current activity level, either sedentary (<30min/week of exercise) or meeting exercise guidelines (>=150min/week of exercise).
• Potential participants should be willing to complete the blood draws and the 12 minutes of moderate-intensity exercise on an elliptical machine.
• Potential participants should be able to speak and read the English language. This is so they will be able to understand the study protocols clearly.

Exclusion Criteria:

• Are allergic to nuts because the snacks provided following the blood draw may contain nut products.
• Do not have transportation and parking (if needed) to lab.

We do not anticipate sharing individual, identified data to other researchers.

Lab processing the blood samples is blinded to participant group.