Final answer:
The cooldown phase of a workout session should consist of light exercise and stretching, aiding in recovery and evaporative cooling.
Step-by-step explanation:
The cooldown portion of a workout session should consist of light exercise and stretching. This helps the body transition back to a resting state, is beneficial for the recovery process, and can help reduce muscle stiffness and soreness. Examples of cooldown activities include slow walking, gentle cycling, followed by stretches that target the main muscle groups used during the workout. These measures are important to prevent an abrupt drop in heart rate and to gradually lower the body temperature, which reduces sweating for evaporative cooling and hence aids in thermal regulation of the body after exercise.