Losing weight is often one of the chief motivations behind taking up any kind of exercise routine, and running is no different. Many of our own FirstRunners started out with the intention of shedding the kilos but have stayed runners even after that goal was achieved.
For those who are struggling to rid themselves of excess body fat, running can be a relatively hassle-free and effective workout that requires very little apart from shoes and determination. Now our fat reserves, by themselves, are useful things – they provide the energy we need for going about our day-to-day activities. When we undertake high-intensity training, however, the body draws its energy from carbohydrates – hence all the pasta parties and emphasis on carb-loading before a race. Wouldn’t it be great, though, if there was a way to burn our own fat during runs instead of consuming additional carbs for energy?
Turns out there may be. Metabolic Efficiency Training (or MET) is a combination of nutrition and exercise techniques that trains the body to use its stored nutrient reserves in an efficient manner and whenever they’re called upon. More specifically, it can help you stabilize your blood sugars, give you steady energy, lose body fat and allow you to run faster at a lower heart rate. Let’s take a closer look.
The crossover concept
For physiological reasons best left to experts, our bodies start switching from fat reserves to carbohydrates for energy and fuel once training exceeds a certain intensity level. The crossover point we need to figure out is the level at which this switch occurs, so that as runners, we can stay below that line to maximize our fat-burning capacities. This point can be measured or defined in terms of pace, speed, watts (on the treadmill) or heart rate during an ME test. By wearing a heart rate monitor, a runner can determine the approximate point of exertion after which the body starts using carbs for fuel. The aim of MET is to teach your body to use more fat (and therefore less carbohydrates) even as you increase the intensity of your training. Achieving this involves a twofold process that regulates both diet and exercise.
Bob Seebohar, Olympic Triathlon Dietitian and MET expert explains that for MET to be effective, one must maintain a workout intensity lower than the rate at which the body starts using more carbs for energy. Secondly, a thoroughly balanced nutrition intake must be followed that has less of refined carbs and more of good fats. Both components are equally crucial and must be followed in tandem.
Working out consistently at ME level (a heart rate lower than the switch over) trains our cellular processes to burn fat on a regular basis. The initial low-intensity training might be really hard to get used to, and you may find yourselves taking longer on your 5K practice runs at crossover heart rate. However, most experts estimate a time period of 4-10 weeks (of 6-7 hours a week of ME training) within which your body can adapt to MET. After this period, your cellular processes will be trained to continue utilizing fat for fuel even as you step up the intensity of the training.
The above scenario where your body continues to burn fat even after you’ve increased intensity can only occur if you aren’t flooding your diet with extra carb during training. Remember, this is not a low-carbohydrate diet, but a balanced one that comprises lean protein, good fats and plenty of fruit, beans and vegetables. Foods that are rich in refined carbs will lead to increase in carb-usage for energy; similarly, foods that cause an insulin spike are to be avoided as they can turn down the body’s fat-oxidizing capacities. This means cutting down on grains, bagels, pasta, sports gels, bars and health drinks with complex sugars, and going for non-grain-based carbohydrate such as fresh or dried fruit, fruit-nut bars, or nut butters.
It follows that because your runs during the MET plan will be at low-intensity, the reduced carb intake will not lead to energy loss or fatigue, as your body will effectively burn your own fat to keep you going.