Pain in Aging Former Athletes, Master's Athletes, and Nonathletes

Inclusion Criteria (General):

* Age: 35 years through 65 years
* Current master's athlete, former competitive athletes, or non-athlete control (see details below)
* Ability to participate in exercise and exercise testing based on the Physical Activity Readiness Questionnaire (PAR-Q+)

Exclusion Criteria (General):

* Currently pregnant or planning to become pregnant during the study
* Currently taking heart rate lowering medications (e.g., betablockers) that would impact exercise testing
* Contraindications to ice such as Raynaud's, cryoglobulinemia, cold urticaria, and/or impaired circulation or sensation
* Fibromyalgia and/or chronic regional pain syndrome (CRPS)
* Myocardial infarction or pulmonary embolism in the last 12 months, active cancer, a pacemaker, or any additional condition or disease that would preclude the individual from being able to perform the tests safely

Participants will be enrolled into one of the following three mutually exclusive groups according to the following criteria:

1. Former Competitive Athlete: Prior participation in competitive sports at the Tier 3 level or above as per McKay et al. (2022): i.e., "national-level representatives who are performing structured and/or periodized training and are developing proficiency in skills required to perform their sport at the highest level; this tier includes individuals participating in Provincial/State or Academy Programs" or higher participation in sport; Not currently participating in any recreational or competitive sports over the last 5 years (Tier 2 or above)
2. Master's Athlete: Currently (within the past year) participating in sports at the Tier 2 level or above (i.e., committed to sports-specific training at least 3 times per week with the intent to compete)(McKay et al., 2022)
3. Nonathlete Control: No prior participation in sport at the Tier 3 (Highly Trained/National) Level or above and not currently participating in any competitive sports (i.e., Tier 2 or above) (McKay et al., 2022) for at least 5 years