It is important that you maintain an adequate level of aerobic fitness to look after your heart. Regular structured exercise will also help maintain a healthy weight and control other risk factors for heart disease. Components of exercise prescription constitute the exercise dose or quantity needed to improve health. Exercising in the correct framework can help you get the most out of your physical activity and maximise your workout. Exercise prescription relies heavily on the parameters comprised in the FITT principle which is used as the building blocks for the foundation of a programme.
The FITT principle, outlined below, should be used when considering or evaluating your aerobic exercise program needs.
Frequency – The first thing to set up is how often you will exercise. You should aim for exercising at least three times per week and aim for most days of the week.
Intensity – You should try to exercise at a target heart rate of 60-85% of the maximum for your age, depending on your fitness level. The exercise undertaken depends on your goals.
Time – Your exercising sessions should last between 20-45 minutes, counting only the time in which you are actually working at your target heart rate. There isn’t one set rule and will typically depend on your fitness level and type of workout you are undertaking. Note: time taken for warm-up should not be included.
Type – You need to do aerobic exercise to improve your cardiovascular fitness. Aerobic exercise is continuous exercise that sufficiently increases your heart rate and can include walking, jogging, cycling, swimming, rowing, riding, and most aerobic classes. Having more than one go-to aerobic activity is important as your body needs variability.
MEASURING YOUR FITNESS USING RESTING HEART RATE
Resting Heart Rate
Your resting heart rate should ideally be in the range of 50-80 beats per minute.
How to Calculate Resting Heart Rate:
- Locate you pulse
- Count the number of beats in 15 seconds
- Multiply your score by four will give you heart rate in beats per minute
Your Resting Heart Rate = bpm
RHR is an excellent predictor of your current fitness levels. The lower your RHR, the better.
TARGET HEART RATES … MORE THAN JUST YOUR PULSE!
Your Target Heart Rate is the optimum heart rate at which you should train in order to get the most effective workout. Target heart rate is generally expressed as a percentage of your maximum safe heart rate. To calculate your target heart rate, you will first need to know your maximum heart rate (MHR).
Maximal Heart Rate
This is theoretically the highest rate a person can attain during heavy exercise.
How to calculate Estimated Maximum Heart Rate:
MHR = 220 bpm – age (in years) = bpm
Target Heart Rate
To determine whether exercise intensity is high enough to increase fitness levels we measure HR whilst exercising. Research has shown that noticeable gains in fitness occur when the HR during exercise is raised to approximately 60-85% of Maximum HR.
Poor Fitness: 60% of Maximum HR
Average Fitness: 70% of Maximum HR
Excellent Fitness: 75%+ of Maximum HR
How to calculate Target Heart Rate:
THR = MHR x % intensity
Example: Jane is 20 years old with relatively poor fitness levels.
THR = (220-20) x 60% = 120 bpm
Now that you know your THR, you can monitor your heart rate to ensure it stays around the most effective value.
Leigh Ashmore (BSc Sports Science, PGradDip Exercise Rehab)
Exercise Rehabilitation Team Leader – Workers Compensation Specialist
Fuminori Katsukawa (2016). FITT principle of exercise in the management of lifestyle-related diseases. Clinical Calcium, 26 (3), 447-451.
Sandra A. Billinger & Pierce Boyne & Eileen Coughenour & Kari Dunning & Anna Mattlage (2014). Does Aerobic Exercise and the FITT Principle Fit into Stroke Recovery? Curr Neurol Neurosci Rep (2015).