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Benefits of strength training: 5 ways lifting weights can improve your metabolism

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Strength training makes every part of us stronger – from our glutes to our metabolism. By priming the body to utilise fuel more efficiently, lifting weights helps us to stay energised on and off the mat. 

Strength training is all about getting stronger. Whether it’s deadlifting dumbbells, improving your squats or holding a lunge, the main purpose of strength training is to put the body under tension so that our muscles repair back stronger. But another significant benefit of lifting weights has to do with your metabolism.

Metabolism is series of chemical reactions designed to turn food into energy and get rid of waste. There are plenty of “metabolism-boosting” products or plans out there, which are often marketed to tap into people’s fear of fat. In many cases, they “work” by speeding up the rate at which food passes through us – having a laxative effect – and raising our heart rate via copious amounts of caffeine

Having an increased or “high” metabolism means being able to access energy quickly from food and getting rid of waste efficiently. A sluggish metabolism, on the other hand, has the opposite effect. Women with polycystic ovarian syndrome (PCOS) are often warned that their condition can hamper their metabolic efficiency, which is why increased body fat can be a common symptom. 

When “normal” metabolism gets disrupted, the risk of developing chronic conditions such as type II diabetes, cancer and metabolic syndrome increases. Metabolic health, therefore, is important.

However, you don’t have to engage with weight or fat loss to improve the way your body operates as a machine. If you want to get stronger, strength training can help you to move better, feel more powerful and – as a byproduct – improve your metabolism.

Here’s how strength training benefits your metabolic system:

Strength training builds muscle

It’s an obvious point, but lifting weights builds muscle. That muscle isn’t just important for helping you move with more ease, though – it also increases metabolism. While exercises such as running can help to burn body fat, they may also decrease muscle size – leading to weaker muscles and unintentional weight loss (muscle is more dense than fat). If you don’t fuel effectively, the body can end up eating into its own muscle stores to keep it going over long distances (think: marathon training). Evidence shows, however, that strength training not only helps to burn excess body fat but also increases muscle size and strength

“By strength training. we increase our muscle mass and more muscle has been shown to be one of the factors that may increase metabolism,” explains Strong Women ambassador, Emma Obayuvana. Emma warns, however, that this effect is “largely based on an individual’s base metabolic rate and body mass,” and therefore isn’t something we can quantify en masse.

Strength training boosts metabolism as a by-product of building lean muscle and strength
Strength training boosts metabolism as a by-product of building lean muscle and strength

Strength training prompts an “after-burn effect”

Whatever your goals are, it’s a fact that strength training burns body fat and builds lean muscle mass. The stronger you get, the more energy you end up burning every day when your body is at rest, with research showing that your metabolism stays elevated for up to 38 hours after a strength training session. 

When we lift weights, our muscles need more energy to operate and that energy is only accessible when oxygen helps to break down fat and carbohydrates. During exercise, we breathe faster and our hearts beat harder to pump more oxygen, fat and carbs into our muscles. When we finish the session, that oxygen uptake remains elevated because our muscles still need those fats and carbs to be broken down to help them repair and return to a rested state. That process is known as “excess post-exercise oxygen consumption” (EPOC), or the “after-burn effect”. 

If fat burning isn’t your goal, you can rest easy in the knowledge that your body is becoming stronger even after you’ve finished working out. Emma points out that it’s crucial to remember that fat and weight loss have little-to-no correlation to how strong you can feel from lifting weights.

Strength training helps to elevate your resting metabolic rate

Your resting metabolic rate (RMR) is the number of calories that your body requires to stay alive. One of the many reasons that gyms and trainers who try to persuade clients to survive on minuscule calorie intakes is such nonsense is that everyone has a different RMR, depending on their muscle percentage and exercise regime. One person’s RMR might be a lot higher than someone else’s, despite them being the same height. That means prescribing a daily intake of 1,250 calories, for example, will leave some people feeling fine and others feeling horrible. Your RMR accounts for up to 75% of your overall energy expenditure if you don’t exercise, but the more you train, the more energy you need to go about your life outside of the gym.

A review of 18 studies found that resistance training was effective at increasing resting metabolic rate, unlike cardio exercise, which had a much smaller impact. It’s worth noting that this is only the case if you incorporate your big, powerhouse muscles and full-body movements into your workouts, because the whole body works harder by engaging a larger amount of muscle. 

Strength training helps you to absorb more nutrients

Having an efficient metabolism isn’t just about burning through fuel faster – it also means being able to properly absorb vital nutrients from that fuel. Emma explains that it enables “our bodies to absorb macronutrients (such as proteins and fats) more efficiently while increasing the rate at which toxins and waste are removed. 

Strength training can help to develop better body image

If burning body fat is something that you’re interested in, then strength training can help you to develop a more mentally-healthy approach to working towards that. Emma suggests focussing on improving your performance and overall strength, rather than your weight or waist: “The more you focus on your strength, the more sustainable the results will be.” She says that while the aesthetic change may be gradual, “your body will change without you feeling discouraged during the journey. It’s a lot more exciting to notice that you’re able to do more press-ups rather than staring in the mirror every day, expecting a change.”

If you’re concerned about disordered eating and exercising, be sure to talk to someone. Check out the eating disorder charity Beat’s website for more information.

If you’re interested in adding more powerhouse muscle-hitting, compound moves to your workouts, have a go at an eccentric press up. Every muscle needs to be switched on to help lift and slowly lower your body – no mean feat! You can find more workout ideas over in the Strong Women Training Club How To library.

Take your fitness up a notch by joining one of the SWTC training plans. Let us know how you get on. It’s time to get strong

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Miranda Larbi

Miranda Larbi is the editor of Strong Women and Strong Women Training Club. A qualified personal trainer and vegan runner, she can usually be found training for the next marathon, seeking out vegan treats or cycling across London on a pond-green Tokyo bike.

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