Study to Warm Up and Cool Down Recreationally Active Males Using Different Protocols.

This semi-randomized crossover control trial was performed between September and October 2020. Data collection took place over the course of 5-weeks with 10 subjects, with one data collection session with all subjects per week (hence, 40 trials total). Baseline gastrointestinal temperature (Tgi) was recorded, and the final Tgi at the end of the heating intervention (Part I), was used as the starting temperature for the current study (Part II).

Part I focused on assessing the efficacy of different heating strategies (Passive heating in a hot environment (60 min), Active heating (30 min) + passive heating (30 min) in a hot environment, Active heating(60 min) in a hot environment, and Active heating (60 min) at room temperature), aiming to reach a core temperature of 38.5°C during a 60-minute period.

Part II focused on cooling the body to a pre-exercise baseline core temperature. Cooling strategies consisted of: 1) Cool vest (18°C) with 500 mL (16 fl oz) ice water consumption, 2) Damp neck towel (24°C) combined with arm (i.e. hand, forearm and half of upper arm) cool water immersion (15°C) and 500 mL (16 fl oz) ice water consumption 3) Combination of cool vest (18°C), damp neck towel (24°C) with arm cool water immersion (15°C), and 500 mL (16 fl oz) ice water consumption or 4) A control with participant sitting in a thermoneutral room (20°C air temperature) without any additional cooling intervention. Thermoneutral water was consumed ad libitum for all interventions in addition to the 500 mL (16 fl oz) ice water consumption for experimental trials (#1-3).

Inclusion criteria

• self-reported healthy
• non-smoking
• uninjured
• active (training five to ten hours per week)

Exclusion criteria

• Participants were screened for fitness using the Physical Activity Readiness Questionnaire (PAR-Q): scoring one or more items as a yes.
• Contraindications to use a body core temperature sensor capsule.