If you’re anything like us, your twenties (and beyond) have ushered in a time where your once-speedy metabolism doesn’t operate the way it did during your teenage years, making it a whole lot harder to keep your body in top nick. As such, many of us have tried different diets and exercises that all promise to boost our metabolic rate. But are they really worth their salt? To find out the best ways to boost our metabolism once and for all, we spoke to Jessica Spendlove, who is the nutritionist and sports dietitian for the GWS Giants, Cronulla Sharks, Giants Netball and Sydney Kings.
What is your metabolism?
Before finding out the different ways to increase your metabolism, you first need to understand what it is. “Metabolism in its most simplistic form is the process by which the body converts food into energy. These processes include those that break down nutrients from our food and those that build and repair our body,” explains Spendlove. She adds, “metabolic rate can be divided into three main components: basal metabolic rate (BMR), which refers to the amount of energy burned at rest and includes the energy required to keep all systems functioning (this accounts for the largest amount of energy expended daily); the second is thermic effect of food, which is the energy used to digest and metabolise what you have eaten; and the third includes the energy used during physical training and is largely dependent on the individual and what their lifestyle consists of”.
The role of your metabolism
In a nutshell, the main role of your metabolism is to keep your body in balance and ensure it is functioning effectively. It does so through two main functions. Spendlove explains that the first phase (catabolism) “is where the body breaks down foods into their basic nutrient forms i.e. carbohydrate, protein and fat. These nutrients, known as macronutrients, can then be used to create energy and provide the building blocks required for growth and repair.” The second phase (anabolism) is where our body is built and repaired. Anabolism requires energy, which ultimately comes from our food, and is used once catabolism has occurred.
What affects how fast your metabolism functions
“Body composition and overall muscle mass are the big factors when it comes to determining an individual’s metabolic rate. Essentially, the more muscle mass you have, the more energy you burn,” explains Spendlove.
In regards to what slows your metabolism down, Spendlove notes, “yo-yo dieting is the worst thing you can do. This is because when you lose weight quickly, you lose muscle mass, and when you gain weight quickly, you gain fat, which is the opposite of what you want when trying to speed up your metabolism.” Also, Spendlove adds that restricting your intake of food and eating too few kilojoules “encourages the body to conserve energy by slowing its metabolic rate”. As to why your metabolism slows down as you age? Spendlove says it’s all down to a reduction of muscle mass. “Generally speaking, people tend to gain fat as they age, partly because the body slowly loses muscle mass.” This increase in fat and decrease in muscle then results in a slower metabolic rate.
Is your metabolism genetically predetermined?
If you’ve spent your life thinking you inherited your slow metabolism from your parents, it might be time to think again. Spendlove explains that while your genetic predisposition can impact your metabolism, “the main factor overall is your body composition and the amount of fat mass vs. the amount of muscle mass. We know muscle tissue is metabolically very active and requires more energy, so focusing on gaining muscle, or retaining muscle is key”.
It’s important to note here that gaining muscle doesn’t necessarily mean bulking or transforming yourself into a bodybuilder, but rather it involves “implementing strategies that are conducive to maintaining or gaining lean muscle mass and losing body fat”. If you’re not sure how to do just that, we recommend chatting with a personal trainer to determine the best exercises for you.
The foods that boost metabolism
In addition to building muscle mass, some foods can assist with boosting your metabolic rate in the short term, namely green tea, caffeine and chilli. Green tea has been touted as a metabolism booster as “there is some scientific evidence out there that suggests green tea may have some fat burning properties,” explains Spendlove. Caffeine on the other hand, “works by stimulating your central nervous system by increasing your heart rate and breathing,” while “chilli or capsaicin, which is the compound that gives chilli its hotness, have been shown to boost metabolism (when about one tablespoon is consumed) as they increase the body’s production of heat,” she adds.
While these foods will give your metabolic rate a boost, Spendlove stresses you shouldn’t expect any miracles from them, especially if you’re boozing all weekend long or if your diet contains processed, sugary and highly saturated fatty foods.
The exercises that boost metabolism
Ultimately, exercise is the main activity that speeds up your metabolism. “In the short term, exercise (particularly high-intensity exercise), boosts your metabolic rate. In the long term, exercising and eating to increase muscle mass will speed up your metabolic rate due to the increased muscle tissue,” says Spendlove. For best results, “the ideal combination for boosting your metabolic rate when it comes to activity is a combination of high-intensity interval training and resistance training”.
Looking for more health and fitness tips? Then check out the workout Jennifer Aniston swears by and be wary of these superfoods that can actually be bad for you.
What are your favourite high-intensity workouts? Share them with us in the comments below.
Main image credit: Getty
Kate started working for BEAUTYcrew in early 2016, first as a contributor, and was then named Beauty Writer in 2017. She loves picking the brains of the industry's top experts to get to the bottom of beauty's toughest questions. Bronze eyeshadow palettes are her weakness and she's forever on the hunt for the perfect nude nail polish to suit her fair skin. Her words can also be found in Men's Health magazine, and she now works in PR.