What is "NEAT"? Non-Exercise Activity Thermogenesis Explained

What is

What is ‘NEAT’?

NEAT stands for non-exercise activity thermogenesis. This means calories burned through movement outside of structured exercise. For example if you go for a run or a workout, these additional calories burned are classed as ‘EAT’ (exercise activity thermogenesis) whereas all movement outside of exercise is NEAT. Getting out of bed, walking around the house, fidgeting, sitting and standing etc.

Let’s look at total daily energy expenditure. Basal metabolic rate is the number of calories you burn at rest. Even if you are asleep your body has processes like breathing and organ function. This is governed by body mass and body composition and is outside of your control on a day to day basis.

Physical activity is the component that you are most in control of. This is split into calories burned through structured exercise (EAT) and calories burned through NEAT.

NEAT is commonly neglected. When someone thinks of exercising to get fit or lose weight the immediate mindset is normally to join a gym. Even calorie calculators often ask how many times per week you workout, not necessarily how much you move on a daily basis. NEAT is however, a larger contributor to total daily energy expenditure (total calories burned) than calories burned through exercise.

Due to rapidly evolving changes in our lifestyle it shouldn’t come as a surprise that people commonly burn fewer calories on average than we used to. We have more desk jobs, more public transport options, more technology such as televisions, games consoles and the internet and even have food delivery apps which allow us to order food from the comfort of our own home rather than leaving the house to buy food and cook it ourselves.

In a physical job, someone could burn a couple of thousand calories per day more than if they were chair bound. This is a significantly higher calorie burn than most people will hit from their standard gym workout, outside of athletes engaging in extreme endurance events. 

NEAT has also been shown to be able to offset fat gain during periods of overfeeding. In one study, when subjects consumed 1000 calories per day above their maintenance needs, fat gain varied 10 fold between subjects. In short, NEAT can act to mitigate the additional calories.

Physical activity has also been shown to be a significant contributor to decreases in metabolism after a period of sustained weight loss (otherwise known as ‘adaptive thermogenesis’).

Other research has also shown that successful weight loss maintainers higher step counts than people who were at a similar BMI who were at the normal weight.

There is a theory that higher levels of exercise can decrease NEAT so the exercise calories burned are not purely additional. This is described as constrained total energy expenditure. A simple example of this would be going for an intense workout but then relegating yourself to the sofa for the rest of the day due to exhaustion rather than moving around like you would do normally. This is one reason why exercising may not create the weight loss stimulus people expect.

To summarise, NEAT is an often neglected form of calorie expenditure. High levels of NEAT could mitigate weight gain during periods of a calorie surplus, help promote weight loss and could also serve as an important tool for weight loss maintenance.

It is free and doesn’t require special equipment or a gym membership. Consider walking more instead of using public transport, take the stairs instead of the elevator, don’t insist on parking in the closest possible space to store entrance, standing up and moving around at regular intervals if you work at a desk etc.

People often say you can’t out exercise a poor diet. Likewise, it is very difficult to out exercise a sedentary lifestyle.

References:

  • Non-Exercise Activity Thermogenesis (NEAT) and Adiposity
  • Non-exercise Activity Thermogenesis In Obesity Management 
  • Long-term persistence of adaptive thermogenesis in subjects who have maintained a reduced body weight
  • The role of non-exercise activity thermogenesis in human obesity
  • Role of Non-exercise Activity Thermogenesis in Resistance to Fat Gain in Humans
  • Long-term persistence of adaptive thermogenesis in subjects who have maintained a reduced body weight.
  • Physical Activity Energy Expenditure and Total Daily Energy Expenditure in Successful Weight Loss Maintainers
  • Constrained Total Energy Expenditure and Metabolic Adaptation to Physical Activity in Adult Humans