Here are some definition of words and phrases used in connection with fitness:

• Aerobic/cardiovascular activity: These are activities where the body is able to supply adequate oxygen to the working muscles, for a period of time. These include running, cycling, dancing, and walking. 

• Maximum Heart Rate: The maximum heart rate is the fastest rate achieved at maximal exercise. It is based on the person’s age. A simple method to calculate the predicted maximum heart rate is given below:

Predicted maximum heart rate = 220 - age

• Flexibility training or stretching: Flexibility training refers to the exercises for the purpose of increasing one’s range of motion. Increased range of motion can improve mobility in activities like sports or daily activities. 

• Strength, weight, or resistance training: According to the American Sports Medicine Institute (ASMI), strength or weight or resistance training is a specialized method "designed to increase muscle strength, muscle endurance and muscle power," The health benefits include improved muscle strength and tone, increased bone density and  healthy weight.

• Set: Set is the number of repetitions a specific exercise is done. For e.g. you can do 12 squats, rest for few minutes and then do another 12 squats.

• Repetition or "rep": Repetition is the number of times to perform an exercise. In the example mentioned above, 12 squats are considered 12 repetitions. 

• Warm up: Warm up exercises are light exercises performed to get the body ready for physical activity. Warm up reduces the risk of injuries and also the pain and aches that come along with an exercise.

• Cool down: Cooling down after exercising means slowing down the level of activity gradually. Cooling down is essential as the body needs time to slow down and it also helps in recovery.