Author: Carlos Lorente-González et al.
Journal: Journal of Human Kinetics (2026)

This summary explains the findings of the study “Physiological Effects of the Cool Vest Jacket on Recovery after a Repeated Shuttle Sprint Ability Test”.

Summary

Using a cooling vest immediately after high-intensity sprints in hot weather helps the body cool down its surface temperature much faster in the first few minutes of rest. While the vest also showed slight, temporary improvements in lowering heart rate and clearing lactic acid, these effects did not last long and disappeared after about five to ten minutes of recovery. Essentially, a cooling vest is a quick way to “reset” an athlete’s surface temperature during short breaks, even if it doesn’t significantly change the body’s deeper metabolic recovery over a longer period.

Purpose of the Study

Researchers wanted to determine if wearing a cooling vest during a 15-minute recovery period after intense soccer-style sprints could improve how quickly an athlete’s body recovers in hot conditions (~32°C/90°F). They specifically looked at:

• Skin temperature: How fast the body surface cools down.
• Heart rate: How quickly the cardiovascular system returns to a resting state.
• Blood lactate: How fast the body clears the “waste products” of high-intensity effort.

Methods

• Who: 11 recreational male soccer players.
• The Test: Players performed a Repeated Shuttle Sprint Ability (RSSA) test, which involved six 40-meter sprints (with a 180° turn) and only 20 seconds of rest between each sprint.
• The Intervention: After the sprints, players rested for 15 minutes under two different conditions:
  1. Cooling Vest: Wearing a vest filled with ice cubes on the front and back.
  2. Control: Resting normally without a vest.
• What was measured: Skin temperature at five different body parts, heart rate, and blood lactate levels were recorded at various points (1, 3, 5, 10, and 15 minutes) during recovery.

Key Results

• Immediate Surface Cooling: The cooling vest significantly reduced skin temperature at the 3-minute and 5-minute marks compared to resting without one.
• Early Heart Rate Drop: In the very first minute of recovery, players wearing the vest had a lower heart rate than those who didn’t.
• Lactate Clearance: Lactic acid levels were lower at the 3 and 5-minute marks for those using the vest.
• The “Vanishing” Effect: By the 10-to-15-minute mark, there were no significant differences between the cooling vest group and the normal rest group for heart rate or skin temperature.

Practical Applications for Coaches & Athletes

• Perfect for Short Breaks: Because the vest’s benefits are most noticeable in the first 5 minutes, it is an ideal tool for halftime, water breaks, or short substitutions where an athlete needs to feel cooler and “reset” quickly.
• Heat Management: In hot environments, reducing skin temperature can lower an athlete’s “perceived” exertion and thermal stress, potentially helping them stay mentally sharp and ready for the next bout of play.
• Ease of Use: Unlike ice baths (which require lots of water and time), cooling vests are portable and can be worn while the athlete is walking or listening to coaching instructions.
• Limitation in Long Recovery: If an athlete has 20+ minutes to recover, the vest provides no extra physiological benefit over standard rest. It is a tool for rapid cooling, not a replacement for long-term recovery protocols.

Key Takeaways

• Fast Surface Cooling: Reduces skin temperature significantly within the first 5 minutes of use.
• Brief Heart Rate Boost: Helps lower heart rate faster during the critical first minute after a sprint.
• Quick “Reset”: Most effective for short recovery windows (under 10 minutes) rather than long rest periods.
• Heat Stress Relief: A practical, portable way to combat the negative effects of playing in high temperatures.
• Limited Deep Recovery: Does not seem to change the body’s deeper metabolic or long-term recovery processes.

Limitations

• Sample Size: The study only used 11 participants, which is a small group.
• Athlete Level: The participants were “recreational” soccer players; elite professionals might respond differently due to higher fitness levels.
• Internal Temperature: The study measured skin temperature, but not “core” (internal) body temperature, which is also a major factor in heat-related performance.

This summary was generated with the assistance of Gemini based on the original article, with the aim of translating the research into practical insights for coaches and practitioners.