Sprinting is one of the best fat-burning exercises out there with so many benefits. By sprinting I don’t mean running/jogging but sprinting flat out. Many of us might think sprinting like Usain Bolt is just for professionals. Many might be afraid of trying to sprint again because decades might have passed since you last sprinted. Sure, jogging and cycling have their place and are good for endurance and breaking down muscle. This for me is the problem, the breaking down of muscles instead of building muscle. Having less muscle mass than before lowers your resting metabolic rate and you will burn fewer calories on a daily basis when resting.
What are the differences between sprinting and jogging?
Sprinting is high-intensity strength training with maximum muscle contraction. This is an anaerobic exercise where you activate your fast-twitch muscle fibers. This is a muscle-building exercise, that compares sprint athletes to marathon runners. Examples of high-intensity exercise include sprinting and weightlifting.
Jogging is moderate-intensity endurance/cardio training. This is an aerobic exercise where you use your slow-twitch muscle fibers. This kind of exercise will break down muscles in the long run, just look at long/intermediate distance runners. Moderate-intensity exercise includes jogging, cycling, swimming, rowing, and hiking just to name a few.
Aerobic vs anaerobic training
Aerobic exercise like jogging uses oxygen through breathing to meet the energy demands of your body. With moderate-intensity training, you will start to breathe faster and deeper for more oxygen to get absorbed in the blood through the lungs. Your heart rate will also go up to transport oxygen and nutrients faster to the muscles. These energy demands are relatively low compared to high-intensity training and there is enough time when doing moderate-intensity training to depend on aerobic metabolism for energy demands. Aerobic metabolism uses oxygen together with carbohydrates, proteins, and fats to create energy (adenosine triphosphate) for the muscles. The byproducts of aerobic metabolism are carbon dioxide and water. This is the preferred method for the body to produce energy and the body can get rid of these byproducts by breathing, sweating, and urinating.
During anaerobic exercise like sprinting the energy demands exceeds the capacity of aerobic metabolism to meet energy demands. This kind of exercise is done within 2 minutes because the body can only sustain high-intensity muscle contraction for short periods of time. The oxygen needed for aerobic exercise is acquired through breathing and gets absorbed in the lungs and transported through the blood to the muscles. This process takes too long, when the oxygen reaches the muscles the sprint is done. During high-intensity training, the lesser efficient anaerobic system will kick in to meet the body’s energy demands. During anaerobic exercise the body must create energy fast for the muscles to function optimally, this energy source is mainly from anaerobic glycolysis. Glycolysis is where glucose (stored as glycogen in muscles and liver) is converted into energy and the high-energy molecule ATP (adenosine triphosphate) is formed. Anaerobic glycolysis does not require oxygen to create energy. Lactic acid, one of the end products of anaerobic glycolysis causes muscle soreness and fatigue. In anaerobic metabolism, only glucose and glycogen can be used to create ATP, whereas, in aerobic metabolism carbohydrates, fats and proteins are used in the presence of oxygen to create ATP. During anaerobic metabolism, far fewer ATP molecules are produced from one glucose molecule.
Something about lactic acid
During high-intensity training, your muscles will fatigue quickly and can only support short bursts of maximum muscle contraction. Anaerobic metabolism uses stored glycogen because it can be quickly acquired and broken down for energy. During this process, lactic acid levels rise quickly in the muscles and during strenuous exercise, the muscle cells cannot get rid of the lactic acid fast enough. An excess build-up of lactic acid slows down muscle contraction and hinders performance, which is why you can only perform at maximum intensity for short periods of time. When you take a breather afterward you give your muscles time to get rid of excess lactic acid which allows you to do another round.
Myokines, what are those?
Myokines are produced and released by the muscles during muscle contractions and are chemical messengers. Myokine production rises with the intensity of muscle contractions, and bigger muscles will also create more of these messengers. Myokines communicate with a wide variety of cells in the body and have receptors on muscle, liver, fat, bone, pancreas, brain, immune, and heart cells. This reflects that myokines have many functions. They are involved in exercise-induced metabolic processes as well as metabolic processes following exercise. They are involved in cell signaling and expression and in tissue repair, regeneration, and maintenance.
The bottom line here is that they are involved in repairing and building muscles and will decrease body fat. During intense anaerobic exercise, the maximum amount of myokines is produced and released compared to aerobic exercise where there are much fewer of these myokines. This is why you get muscle growth with sprinting.
Slow twitch vs fast twitch muscle fibers
All skeletal muscles have slow-twitch and fast-twitch muscle fibers in them, but the proportion of these fibers might differ. Somebody who doesn’t exercise will have a more or less 50/50 ratio of these muscle fibers. When you do exercises that use mainly powerful movements like sprinting, then you will have a higher percentage of fast twitch muscle fibers. Doing mainly endurance-type training like marathon running you will have a much higher percentage of slow twitch muscle fibers.
Slow twitch fibers; these fibers are aerobic in nature and contain more mitochondria and myoglobin. Mitochondria are found within the muscle cells and are responsible for producing most of the cell’s ATP while using oxygen. This process is normal cellular respiration. Myoglobin is an oxygen-binding protein. Slow twitch fibers are referred to as Type I or red fibers. This is because of their blood supply. These fibers are smaller than fast twitch and produce less power. They can sustain ongoing moderate exercise for long periods of time and takes a long time to fatigue. They also play a big role in maintaining body posture.
Fast twitch fibers; are mostly anaerobic in nature and are involved in strong powerful/quick movements. They are bigger than slow twitch fibers. Fast twitch fibers contain very little mitochondria and blood vessels. These fibers easily fatigue and can only sustain anaerobic exercise for short periods. Fast twitch fibers are referred to as type II fibers and are white because they have less blood supply to them.
Anaerobic heart rate zone
Sprinting will up your heart rate into the anaerobic heart rate zone. This is where your body can not get enough oxygen for aerobic metabolism and needs to tap into anaerobic metabolism. This zone is between 80 and 90% of your maximum heart rate. Maximum heart rate differs between people and you need to know what yours are to be able to determine in which heart rate zone you exercise. Remember your heart rate max will decline with age. Sports watches make it easy and fun to exercise and control your heart rate and make sure you train right.
Conclusion
Everyone has his or her preferred exercise that they like to do. But many times when you are trying to lose weight the results just aren’t there by doing the kind of exercise that you like. Sports or track athletes always look fit, because they do it professionally. They basically train most of the day, or a big part of it and you can’t really compare yourself with them. Most people just don’t have the time for training regularly or for long periods of time.
Lots of people do jogging and cycling as their exercise of choice. Those kinds of exercises are good for losing weight as all endurance training, but as said before they break down muscle as well. Your body releases the hormone cortisol while jogging which has a catabolic effect and breaks down muscle over time. What happens when you get sick or injured and struggle to get into an exercise routine again? When this happens you will start to gain weight again quickly, because you lost muscle mass and lowered your resting metabolic rate. So, you burn fewer calories now when at rest. On the other hand, when you switch to sprinting, things might look different. This is also ideal for very busy people because a sprinting session shouldn’t take longer than about 20 minutes. This high-intensity exercise will build muscles and when you have been doing it for long enough will give you an athletic physique who doesn’t like an athletic body? When jogging your RMR (resting metabolic rate) will be elevated for a few hours after training, but with high-intensity training, your RMR could be elevated for days. This is how long your body takes to repair and build muscles and there is also an ‘afterburn’ effect where your body needs to take in more oxygen to replenish oxygen levels in your body. You will be burning calories in your sleep! Even if you get injured or sick it will take a longer time for you to gain weight, because of your higher RMR.
