Metabolic Rate: What is it and what affects it
What is metabolic rate
The topic of metabolism is relatively straight forward. Our metabolic rate is essentially our general level of calorie burning (like the revs on a car - the higher the revs the more fuel you use). Our individual metabolic rate influences how fast we break down and use the food we eat and also how exercise affects our calorie burning potential, so it is very relevant. A person's current metabolic rate can be influencedin the short and long-term.
What factors affect metabolic rate
Metabolism is affected by nutrition (due to the thermal affect of food), which means that as we break down food the process releases heat and our metabolic rate increases. This is why small, regular meals are generally recommended because of the benefit to maintaining a relatively high and constant metabolic rate.
Hydration also affects metabolism, though to a smaller degree than nutrition. In order to encourage the liver to focus on firing the metabolism rather than water retention, it is advised that you stay well hydrated and consume around 2 litres of water a day (plus more if exercising).
Long term changes to metabolism
The real solution to your metabolic rate in the long-term, is weight training and maintaining lean muscle mass on your body. Muscle burns more calories than fat (73 more calories per kilogram per day, to be exact), so the more muscle you build, the higher your resting metabolic rate (RMR) will be. Every bit of muscle that you gain is like a little factory that burns calories for you 24 hours a day, 7 days a week. This is the only way to increase RMR, which accounts for 60 to 70 percent of the calories you burn daily. When I say 'build' muscle I am not talking size here by the way, I am referring to muscle tone, dense, lean muscle tissue. Something that is very achievable in your 40's, 50's and 60's.
Short term changes to metabolism
There are ways to temporarily increase your metabolic rate and obviously these are just short-term but still worth knowing and utilising:
- Different aerobic activities burn different quantities of calories, but the important thing is to raise your heart rate and sustain the activity for approximately 30 minutes, this supports a metabolic boost.
- Believe it or not, spices like chilli are thought to raise metabolism by up to 50% for up to three hours after eating, due to increasing your heart rate. But before putting the local Indian takeaway on speed dial, work out which curries have the lowest calorie and fat content and make your own. (You can add these in your Personal Recipe Book in the Recipe Club).
- Swap your daily cuppa for green tea - there's evidence that it contains antioxidants that speed up metabolism.
- Chill out - research shows that being very cold can increase metabolism by up to 20%.
- Have a sauna - being very hot is also thought to boost metabolism by about 20% (but check you don't have any underlying medical problems that mean you shouldn't go in saunas or steam rooms).