This is a study of the effects of acute, exhaustive exercise on pro-resolving and pro-inflammatory responses in healthy, trained and untrained adults.

The study requires one visit (a second, optional visit may occur). At the visit, participants will have blood drawn at several time points and also perform an exhaustive bout of treadmill exercise. Differences in specialized pro-resolving lipid mediators (SPMs) and other measures of inflammation and resolution over time will be characterized.

Inclusion Criteria:

• Willingness and ability to provide informed consent and participate in PRESPIRE
• Able to read and speak English adequately to provide informed consent and understand verbal and written instructions. (the diet and sleep questionnaires are not validated in languages other than English)
• BMI < 27kg/m2
• Untrained: self-reporting no more than 1 day per week of regular exercise (inclusive of walking >5,000 steps daily and commuting via bicycle).
• Trained: self-reporting at least 4 hours of aerobic exercise / moderate or greater intensity physical activity weekly for the past year.

Exclusion Criteria:

• Anti-platelet medication use
• Chronic inflammatory or connective tissue disease
• History of bleeding or clotting disorder
• Immunological deficiency
• Diabetes mellitus
• Stage 2 or greater hypertension on screening
• Cardiovascular disease
• Chronic obstructive lung disease
• Anemia (hemoglobin <13g/dL in males or < 12 g/dL in females)
• Active smoking
• >5% body weight change over the past 6 months or plan to gain/lose weight during the study
• Platelet count <100,000
• Use of omega-3 fatty acid supplementation within 3 weeks of study participation
• Use of drugs or supplements known to inhibit COX-1/COX-2/lipoxygenases
• Corticosteroid use
• Use of beta-blocker medications
• Use of alpha-blocker medications
• Use of NSAIDs or aspirin within 2 weeks of study participation
• Vaccination within 2 weeks of study participation
• Pregnancy (a state of relative immunological deficiency)
• Any other cardiovascular, pulmonary, orthopedic, neurologic, psychiatric or other conditions that, in the opinion of the local clinician, would preclude participation and successful completion of the protocol.
• Any other illnesses that, in the opinion of the local clinician, would negatively impact or mitigate participation in and completion of the protocol

Data sharing will be considered, however the study team does not anticipate data will be made public outside of publication.