How Does Exercise Impact Weight Loss
Our body weight depends on our balance of Energy intake and energy expenditure i.e. on how much food we take and how much energy we use up in our daily activities. Energy intake depends on the amount and form of food, while Energy expenditure depends on the Basal Metabolic Rate (BMR) and Physical activities.
If our energy intake is more than expenditure, then there is a positive energy balance and weight gain results.
The energy expenditure depends on a number of factors:
- Starting body weight
- Basal metabolic rate
- Physical activity - which can vary in frequency, intensity, duration and type of activity.
For example, one honey glazed doughnut provides energy equivalent to that needed to walk 30 mins at 30 mph.
If the person walks longer (if 60 mins instead) then there will be a negative balance and weight loss results. However, after an initial weight loss, the weight loss plateaus and there is no further weight loss because when the body weight drops, the basal metabolic rate also decreases, so there is less energy expenditure.
If exercise is stopped, weight gain will result at a slightly greater pace.
Therefore, to end the plateau, one needs to continue to decrease energy intake OR increase energy expenditure by restricting calories further or increasing the intensity or duration of exercise.