Ever wondered if you should be focusing on your diet more than exercise to lose weight or vis-versa? Here's an overview of the contributions of each.
Just passing the half way point for 2017 has most of us re-evaluating our new years resolutions, and a lot of us begin to wonder, ‘what am I doing wrong?’ The big question, is it my diet or my exercise? As a sports professional, I’ve heard it all. At one point, I had a rather heated discussion with previous co-worker who was of the opinion that when it comes to females, women shouldn’t exercise at all and should just stick to dieting for both weight-loss and health purposes! 😠 And although the benefits of exercise can’t be denied, we still get asked this question a lot, so let’s look at this objectively.
The main characteristic of weight-loss plans (either diet or exercise, or both!) is that they provide an imbalance between energy expenditure and energy intake. Which is pretty straight forward - if you consume more energy than you expend, regardless of the diet or exercise regime you're following, you'll gain weight. Period. If you expend more energy than you consume, the end result will be weight-loss. Period. And of course, if you consume the same amount of energy as you expend, you’re in an energy balance, in which case you'll maintain your weight. Because of this, dieting always seems like the easier option for so many people because no matter what a person’s genetic makeup and metabolism, anyone who stops eating is guaranteed to lose weight. But there is a common saying among health and fitness professionals about reaching your weight goals, 'The hard work is not done in the gym, it's in the kitchen'.
The problem is, there are so many fad diets out there, which one then is the best to choose when wanting to lose weight? Well, that’s a discussion for another day. But in one of the largest and longest-run weight-loss studies conducted, different weight-loss diets with varying compositions of fat, protein and carbohydrate were investigated for their influence on weight-loss. Over 2 years, the participants lost an average of 7% of their total body weight, though only about 50% were able to maintain their new weight for the full duration of the study, and there were minimal differences found between the different diets. Similar results were found in another meta-analysis, which showed there is no difference between the different macro proportions in each diet, rather, whether the individual could could adhere to the diet. So, what does this really mean? It means that reduced-calorie diets result in clinically meaningful weight-loss regardless of the macronutrient proportions recommended. The tricky part then, is working out what proportions of macronutrients works well for your body, and understanding how much of those macros your body needs to be in energy balance.
On the opposite side of the room is exercise. The health benefits of exercise are well-recognized, including a reduction in risk factors for cardiovascular disease and type 2 diabetes, not to mention the benefits for mental health as well. In terms of weight-loss, the effects of exercise on fat-loss is much more consistent, and is independent of dieting. This is discussed in more detail in a great review by Elder and Roberts (2007). Overall, they found that people who keep up with 90 minutes of physical activity each day lost the most weight without any prescribed dieting change. Which is understandable; the more exercise you do, the more energy you expend. To most people though, just the thought of this amount of exercise on a daily basis sends people into a sweat!
What this boils down to making sure you balance your exercise with your diet. And a great example of this is looking at the amount of energy in a small, 100g chocolate bar. Since my favourite is Snickers, let’s use this for an example. 100g of Snickers is approximately two bars (or a twin pack!). This provides approximately 500 calories (2200kJ), and it is quite possible to consume 100g of chocolate in one minute. This is enough energy to fuel the body of a sedentary office worker for around 5 hours with no need for other food. So in order to burn this off, you could try a 7 km run, or a 90 minute brisk walk. Or you could just not eat the chocolate bar in the first place... you know what they say, 'Don't do the crime if you can't do the time'.
So what's the overall consensus? Finding a healthy balance of both is the best way to maximise your overall health, which will boost your weight goals, whatever they may be. Finding that balance between the two that you are able to maintain long-term is what will make the chore of exercising less like a chore, and the struggle to maintain a healthy diet less of a struggle, and more of a lifestyle.
Having finished her Masters in Human Nutrition at Deakin University, Sarah, our in house Nutritionist has jumped onboard to help answer the common questions we are asked as trainers, coaches and health professionals.