Role of Physical Activity in Weight Management

Exercise contributes to daily energy expenditure, which is the number of kilojoules a person burns. Each day exercise can help to balance out the energy we consume from our food intake.

The duration, frequency and intensity of exercise are factors to consider when estimating the number of kJs burned and how physical activity and specific types of exercise can play a role in weight management.

The role of exercise

Exercise plays an important role in how much energy you burn each day. The next video will help you to better understand the role of exercise in weight management.


Let’s talk about the role that exercise plays in weight management.

Exercise can help to balance out the energy we consume in our diet.

Health professionals recommend adults do between 150 and 300 minutes of moderate activity per week or 75 – 150 minutes of vigorous activity per week.

You might like to do a combination of the two.

Moderate activity includes fast walking, cycling and easy swimming.

Vigorous activity is where your heart beats rapidly and you sweat more.

Vigorous activity includes running, fast swimming or heavy weight training.

It is recommended that you do at least two days of strength training per week.

To find out how many kilojoules you burn during exercise, try an online exercise calculator.

It will calculate how much energy you have used based on the duration and intensity of exercise in relation to your age, height and weight.

Being active can help you to achieve your weight loss goals, or maintaining a healthy and lifestyle.

How much exercise is needed for weight management?

Recommendations are for adults to do 150–300 minutes of moderate and/or 75–150 minutes of vigorous activity per week. Two days each week should include strength training, preferably spread over 5 days.

Overall, this equates to approximately 30–60 minutes a day of moderate physical activity/exercise.
Or 15–30 minutes a day of vigorous physical activity/exercise.

However, for weight loss, aiming for the higher end of these ranges is more beneficial. It can be hard to do the amount of exercise needed for weight loss if your energy intake from food does not decrease at the same time.

To put this into perspective, if you were to walk at a brisk pace for 60 minutes you would burn approximately 1200kJ which is the equivalent of a small fries from a fast-food restaurant. If instead you chose to run at a moderate pace for 60mins, you would burn more than twice this amount. Many takeaway meals contain more kilojoules than you would burn in 60mins of running. To burn off a consistently poor diet, you would need to do a high amount of exercise every day of the week and this amount of exercise is hard to maintain.

You also need to remember that a poor diet is not just excess kilojoules, it is also excess intake of unhealthy nutrients such as saturated fat and added sugars which have an independent effect on health, so exercise doesn’t counteract the negative effects of excess intakes of these nutrients.

Please note: anyone commencing a new exercise program should always consult their medical practitioner or exercise professional.

Different types of physical activity/exercise

What activities are classed as moderate?

Anything that is not exhausting, and you get light perspiration e.g., fast walking, easy bicycling, easy swimming.

What activities are classed as vigorous?

This is where your heart beats rapidly and you sweat more than lightly e.g., running, football, soccer, vigorous swimming, squash, heavy weight training. Strength training includes activities that build strength, endurance and size of muscles using resistance such as lifting weights or doing push-ups.

For how long?

Minutes of physical activity can be completed in a number of ways e.g. in 30–60 minutes blocks or in small chunks of 10-minute blocks.

Log Book: Exercise tracking


Tracking exercise is a great way to find out just how much energy you are burning during exercise. This can be important when trying to work out how many kilojoules you need to eat each day.

        1. Pick an exercise that you do regularly or have thought about starting up and use one of the links below to work out how many kilojoules you would burn for an amount of time that you are likely to do, or have recently done, this exercise for.
          Calorie King: View the Calorie King tool
          My Dr: View the My Dr tool
        2. Record the type of exercise, the duration and the kJs burned in your Log Book.

(Note: there are also many free mobile apps that also calculate exercise).

Incorporating exercise every day

It is not only specific exercise sessions that are important to incorporate into everyday life, there are also many benefits to making your usual daily activities more physically active. Examples of how you can incorporate exercise into everyday life:

      • Take the stairs instead of the lift or escalator
      • Make your travel more active – for short trips walk, ride, or skateboard instead of the car
      • Park further away so you add in extra walking time
      • Take scheduled activity breaks from your desk to go for a short walk
      • Do more housework or gardening
      • Stand while talking on the phone
      • Walk around the house while brushing your teeth

Incorporating exercise every day

Common barriers to exercise and ways to overcome them

Common barriers

There are a number of common barriers which affect people’s ability to perform exercise. Some of these include:

      • lack of time
      • lack of space
      • cost
      • access to facilities or walking/bike tracks
      • family/work commitments
      • health conditions
      • lack of motivation

Overcome barriers

There are ways to overcome many of these common barriers. Consider the following:

Lack of time

      • Could you break it up into smaller 5–10 minute sessions throughout the day?
      • Could you wake up earlier?
      • Could you do something in your lunch break or after work?


      • Could you use free exercise apps on your smartphone or watch YouTube videos?
      • Could you use local walking tracks or sporting grounds?
      • Could you use household items such as cans of soup for strength training or rope for skipping?
      • Could you do body weight exercises?
      • Could you borrow or buy an exercise DVD that can be replayed?

Access to facilities or walking/bike tracks

      • Could you invest in equipment for the home such as a stationary bike?
      • Could you use YouTube videos or fitness apps on your smartphone for ideas for at home exercises?
      • Could you walk around your backyard?
      • Can you make yourself move around and be active in advertisement breaks on TV?
      • Could you use park benches for tricep dips or squats?

Family/work commitments

      • Could you include family in your exercise activities?
      • Could you incorporate physical activity into work? For example, taking the stairs or going for a walk with colleagues at lunch time?
      • Could you get a standing desk?

Health conditions

      • Could you check with a medical doctor and ask who you should see for appropriate advice?

Lack of motivation

      • Could you exercise with a friend or family member?
      • Could you join a local exercise facility?
      • Could you put some affirmations / motivational statements around the house?
        For example, ‘exercise makes me feel alive’, ‘exercise is a time to bond with family’, ‘I love how I feel after exercise’.
      • Could you listen to music while you exercise?

Calculating your physical activity level (PAL)

PALs are used to define the level of activity that an individual undertakes and help determine their energy expenditure.

The table below can be used as a guide to determine what level of activity you currently fall under. It is used in the calculations that we did in Week 2 to work out your total energy expenditure (TEE).

[table id=6 /]

Log Book: Current level of activity?

We now would like you to record your activity level based on the descriptions given in the table below.
This will give you an idea of how active you are. You can use this as a starting point to improve over time.

      1. Using the table below as a guide, determine what level of activity you currently fall under.
      2. Record your Activity Level and your PAL in your Log Book.

[table id=7 /]

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