Weight loss is a complicated topic that’s filled with many opinions, fad diets and at times, misinformation. There’s often an assumption that “one-size-fits-all”, and the methods that were effective for one person will work for everyone else. If only it was that easy…
You should be aiming to achieve an “energy in / energy out” balance. This means balancing the food we consume to give us energy, to power us appropriately for all the activities that we do during the day. Ideally, if we took an average across several weeks, the input from our diet will match the output from our activities without a significant deficit or excess present.
But we can delve into it deeper with a Metabolic Efficiency Test. This test tells us the exact energy system your body wants to use when it generates power during the day.
The test works by analysing your oxygen and carbon dioxide while you’re at rest and during an exercise test (eg. walking on the treadmill). A poor lifestyle (overtime) often pushes us towards using the glycogen pathway (carbohydrates and sugars), and we become less efficient at using fats and lipids for fuel. Regularly the lifestyle factors lead to a diet with excessive carbohydrates, and too little exercise causing a reduction in aerobic capacity, VO2max and lean muscle mass.
You can see in the first example on the right, this 30yo female has only small useability to use fat while at rest – sitting at only 20%. During their exercise test, the small orange line also shows poor use of fat across a range of heart rates, while the strong blue lines shows a heavy reliance on carbohydrates and sugars for power while they exercise.
In the second example lower on the right, another 30yo female has good fat burning utilisation at rest – this time it’s 63%. She burns fats and lipids very well during exercise, shown by the orange that sitting above the blue (carbohydrate) line for most of her heart rates.
In both examples, you see that fat is best utilised at the athlete’s lower heart rates. It’s a common mistake made by many people when trying to lose weight, that they train too hard and their heart rate is raised into the wrong zone and they end up training in the wrong energy pathway.
For most people, the average heart rate that burns the most fat is 60-70% of their maximum heart rate. However, with a Metabolic Efficiency Test, we can now assess this and provide you with an individualised training program.
With or without the metabolic testing being performed, we recommend seeing an exercise specialist to help you set realistic goals and expectations. Together with an exercise program tailored for you (incorporating aerobic and strength training), our Exercise Physiologists are the exercise experts you need to see to reach your weight loss goals.
It’s also essential that you have your dietary intake correct, and we strongly suggest that an experienced dietitian is with you on your journey.
For more information, please visit our other Metabolic Testing pages:
High performing athletes may often describe “hitting a wall” when pushing themselves during training or competition. This occurs at the depletion of their glycogen (carbohydrate) stores, which causes a sudden onset of fatigue and loss of athletic performance. Performing too close (or above) your anaerobic threshold will bring this effect on quicker, as at these high heart rates most athletes have moved beyond fat metabolism as a fuel and are relying on carbohydrate stores.
Weight loss is a complicated topic that's filled with many opinions, fad diets and at times, misinformation. There's often an assumption that "one-size-fits-all", and the methods that were effective for one person will work for everyone else. If only it was that easy...
You should be aiming to achieve an "energy in / energy out" balance. This means balancing the food we consume to give us energy, to power us appropriately for all the activities that we do during the day. Ideally, if we took an average across several weeks, the input from our diet will match the output from our activities without a significant deficit or excess present.