Work Design Interventions for Older Workers During Consecutive Days in the Heat

The goal of this project is to compare different ways to schedule a workday to see if older workers should follow a specific work protocol to reduce strain on the heart and muscles across two consecutive days of work. Participants will come to the lab a total of six times. During four of the visits participants will complete a box carrying task, simulating unloading a delivery truck. This will take place in a hot and humid room to simulate being outdoors during the summer.

Inclusion Criteria: * Healthy individuals * 18-29 years old and 40-65 years old * Completes at least 120 minutes of moderate to vigorous physical activity each week for at least the past 4 weeks * Resistance trained or have recently held a job involving box carrying or a similar task Exclusion Criteria: * History of cardiovascular, metabolic, respiratory, neural, or renal disease * Hypertensive (systolic blood pressure \> 139 mmHg or diastolic blood pressure \> 89 mmHg) or tachycardic (resting heart rate \> 100 bpm) during the screening visit * Current nicotine use or previous use within the past 6 months * Current of previous musculoskeletal injury limiting physical activity * A positive pregnancy test at any point during the study * Currently breastfeeding * Study physician discretion based on any other medical condition or medication