Frequency, Intensity and Duration of Exercise

Frequency, Intensity and Duration of Exercise
For most people the hardest part of exercising is just getting started. Hectic schedules and lack of time certainly contribute to the excuses. But for many people, lack of basic workout knowledge intimidates them and prevents them from even getting started.

It’s easy to understand why some feel overwhelmed about beginning a new fitness routine. Virtually every day the media is bombarding the public with the latest “diet research” often times contradicting what may have been reported just weeks earlier. And infomercials swear that 20 minutes of this or 15 minutes of that is all that is required to look like a Hollywood star.

With so much information (and misinformation), it can be hard to decipher what fitness regimen will really deliver results. But truthfully, it’s not difficult at all to determine what workout will provide health benefits.

An easy way to get started is utilizing the F.I.T.T. principle. This acronym stands for Frequency, Intensity, Time and Type.

Frequency: As you might expect, this refers to how often you will exercise. After any form of exercise is performed your body completes a process of rebuilding and repairing. So, determining the frequency of exercise is important in order to find a balance that provides just enough stress for the body to adapt and also allows enough rest time for healing.

Intensity: Defined as the amount of effort or work that must be invested in a specific exercise workout. This too requires a good balance to ensure that the intensity is hard enough to overload the body but not so difficult that it results in overtraining, injury or burnout.

Time: Again, this is rather self-explanatory. Time is simply how long each individual session should last. This will vary based on the intensity and type.

Type: What type of exercise will you be doing? Will an exercise session be primarily cardiovascular, resistance training or a combination of both? And, what specific exercises will you perform.


Now you know the F.I.T.T. principle so planning a workout program and getting started should be a breeze. The ACSM (American College of Sport Medicine) has F.I.T.T. guidelines both for cardiovascular work and strength training. For cardiovascular benefits, they recommend exercising for a frequency of 3-5 times per week, at an intensity equal to 60-85 percent of your maximum heart rate for a time of 20-60 minutes. For strength straining they recommend working out a minimum of two times per week at an intensity that is equal to 70-85 percent of your one rep maximum (maximum weight you can use for one rep) for 8-10 reps and 1-3 sets.

Planning a new fitness routine by breaking it into the four F.I.T.T. principle pieces allows you to quickly create a workout plan that will truly provide you with results.

For beginner exercisers choosing the Type of exercise may be the best place to start mapping out your routine. After all, if you have the perfect frequency, intensity and time but hate the actual exercise then you’ll never do it. So, start with something you like. This may be walking, biking, swimming or something else.

Next determine the Frequency. Consider how much time each week you truly will devote to this workout. Be realistic. There’s no purpose in setting expectations so high that you likely will fail. Remember, the ACSM guidelines are 3-5 times per week, so a good start would be three days.

If you are very limited in your schedule then determining your Time would be the appropriate next step. Otherwise, choose your Intensity level, which will help determine how long your workout session should be. For example, a higher intensity will typically provide more benefit (such as burning more calories in a shorter amount of time). So, choosing to jog may require only 30 minutes of commitment versus walking which may require 45-60 minutes.

Here’s a quick example of both a cardiovascular and resistance workout program that utilizes the F.I.T.T. principle. Walk (Type) at 4 MPH (Intensity) for 45 minutes (Time) four times per week (Frequency). Perform exercises with dumbbells (Type) at 70% of your maximum 1 rep strength (Intensity) for 8-12 reps (Time) 3 times per week (Frequency).

That’s all there is to it. Now get out there and get FITT!