It is possible to enhance the effects of regular physical activity by altering the duration, frequency, intensity, or progression of exercise. Match the situations to determine whether they are describing increasing duration, frequency, intensity, or progression of exercise: - Bill was swimming for 30 minutes, 3 days per week and recently increased that to 45 minutes, 3 days per week - Sonya was participating in one aerobics class per week and recently increased that to two aerobics classes per week - Erin was walking on the treadmill at a rate of 3 miles per hour for 60 minutes and recently was able to increase her rate to 4 miles per hour for 60 minutes - Chris used to do 30 minutes of cardio at 50% of his max heart rate 2 days per week and has gradually increased his performance such that now he is exercising for 60 minutes at 80% of his max heart rate 4 days per week A. Progression B. Intensity C. Frequency D. Duration

 - Bill was swimming for 30 minutes, 3 days per week and recently increased that to 45 minutes, 3 days per week: D. Duration

- Sonya was participating in one aerobics class per week and recently increased that to two aerobics classes per week: C. Frequency

- Erin was walking on the treadmill at a rate of 3 miles per hour for 60 minutes and recently was able to increase her rate to 4 miles per hour for 60 minutes:  B. Intensity

- Chris used to do 30 minutes of cardio at 50% of his max heart rate 2 days per week and has gradually increased his performance such that now he is exercising for 60 minutes at 80% of his max heart rate 4 days per week: A. Progression

Explanation:

Duration refers to the amount of time accumulated in a specific physical exercise program (in this case, swimming), which is measured in a given time unit like minutes or hours. Moreover, the frequency can be defined as the occurrence/practice of a given physical activity (in this case, aerobics classes) that is repeated at specific intervals of time. Intensity refers to the speed/workload of a given exercise or training session. Intensity can be divided into two forms: 1-absolute intensity, which is expressed as a percentage of an individual's maximal aerobic capacity, and 2-relative intensity, which is the percent of one repetition maximum for each exercise. Finally, progression is the rate of increase of the intensity, frequency and duration of physical activity from the initial to the maintenance stages (the progression stages include initial, improvement and maintenance stages). Progression is dependent on diverse factors inherent to the individual, i.e., the tolerance to exertion, the objective of the physical exercise, and his/her age.