“Shut your mouth and open your legs.” This sentence succinctly illustrates the essence of weight loss – reduce caloric intake and increase caloric expenditure. If you want to lose weight, you need to burn more calories than you take in. “Keep your mouth shut” means eating a healthy and reasonable diet, avoiding foods that are too oily and sugary, and controlling the total caloric intake. “Spreading your legs” refers to increasing calorie consumption through additional exercise. Many people have taken action in order to lose weight, and most people choose running, a simple and easy exercise. Today, we will discuss how running can achieve better fat loss results.
First, we need to understand the energy supply system of the human body.
Phosphagen system: consists of ATP and CP. It is characterized by small total amount, short duration, lasting about 6-8 seconds, fast output power, no need for oxygen, and no lactic acid production. This system plays a decisive role in short-term racing or maximum force sports.
Glycolysis system: The process of anaerobic decomposition of glycogen or glucose to produce lactic acid and the synthesis of ATP through substrate phosphorylation is called anaerobic glycolysis. Under normal physiological activity, skeletal muscle mainly obtains energy from aerobic oxidation, and glycolysis is of little significance. During high-intensity exercise (such as 400-meter and 800-meter runs), when a large amount of CP is consumed and aerobic metabolism cannot meet energy needs, glycolysis will be strengthened. The maximum speed is reached in 30-60 seconds and can be maintained for 2-3 minutes.
Aerobic oxidation system: Under aerobic conditions, sugar, fat, and protein are completely oxidized into water and carbon dioxide, and the process of releasing a large amount of energy is called aerobic oxidation. Its characteristic is to supply energy to the body in the resting state or during low-to-moderate intensity exercise. The products of aerobic oxidation are water and carbon dioxide, which have less impact on the internal environment of the body. Moreover, this process does not produce lactic acid, that is, no muscle soreness will occur. The aerobic oxidation of sugar mainly refers to liver glycogen, which can sustain high-intensity exercise for about 1.5-2 hours; the aerobic oxidation of fat provides energy for a longer time and is the main material basis for low- and medium-intensity exercise. Protein participates in energy supply during intense exercise longer than 30 minutes, but it does not exceed 18% of the total energy consumption.
After understanding the main energy supply system of the human body, the most important thing for people who want to lose fat is to mobilize as much fat as possible to provide energy for body movement. The process in which the fat stored in fat cells is hydrolyzed by lipase to release fatty acids and enters the blood circulation for uptake and utilization by various tissues throughout the body is fat mobilization. During exercise, skeletal muscle oxidizes fatty acids relying on triglyceride hydrolysis and uptake of plasma free fatty acids (FFA). Therefore, if you want to consume more fat, you must mobilize and utilize as much FFA as possible.
Let us discuss how to use plasma FFA more effectively and increase the proportion of fat energy supply, so as to achieve better fat loss:
- Moderate to low intensity exercise intensity and relatively long exercise duration
During long-term exercise with an intensity of 60-70% of the maximum oxygen uptake and more than 20-30 minutes, arterial blood FFA continues to slowly increase, and the proportion of muscle cells absorbing plasma FFA for energy increases, such as exercise 40, 90 , 180, and 240 minutes, the percentages of fatty acid energy supply in total energy consumption were 37%, 37%, 50%, and 62% respectively.
Heart rate is one of the indicators that reflects exercise intensity. Simply put, the higher the heart rate, the greater the exercise intensity.
Simple calculation formula for maximum heart rate: HRmax= 220-age
The heart rate level corresponding to low-to-moderate intensity exercise is: 60%-80% of the maximum heart rate.
If you are 30 years old, the corresponding aerobic heart rate is: 114-152 beats/min
If the heart rate is too low, the best fat loss effect will not be achieved. If it is too high, anaerobic energy supply will be enhanced, fatigue will occur quickly, exercise cannot be sustained for a long time, and lactic acid will accumulate. Runners who are qualified can use a heart rate belt or heart rate monitor to monitor their exercise heart rate, and runners who do not have the corresponding equipment can also use self-measurement of their pulse.
From the curve in the figure above, we can see that aerobic metabolism exists from the beginning of exercise, so it does not mean that fat begins to be burned only when the exercise time exceeds 30 minutes. Therefore, regardless of the basic exercise ability of people who want to lose fat, as long as they start moving, they will consume fat to varying degrees.
The above table shows the relationship between plasma FFA concentration and exercise time. It can also be clearly seen from the figure that as exercise time increases, the plasma FFA concentration gradually increases, and the amount of FFA absorbed and utilized by skeletal muscles also increases accordingly.
Therefore, if you want to achieve better fat loss results, you should try to extend the exercise time as much as possible according to your own physical condition, and strive to exercise for more than 20 minutes each time.
- Increase endurance training
Among sports training, endurance training has the most obvious impact on human skeletal muscle fatty acid metabolism, because endurance training can increase the energy used by skeletal muscles to use fatty acids for energy. Endurance training can increase the output per minute, increase the content of hemoglobin and myoglobin, increase the density of skeletal muscle capillaries, and improve the oxygen supply capacity of skeletal muscles; on the other hand, endurance training can increase the mitochondria in skeletal muscle cells. The increase in number and volume will increase the activity of enzymes located in mitochondria, which will increase the ability of skeletal muscle to metabolize and utilize oxygen. Both will increase the ratio of fatty acid oxidation for energy during exercise.
Here are several training methods for increasing endurance for your reference:
1) LSD training method
LSD, that is, Long Slow Distance, long-distance low-intensity jogging, this method can effectively train the energy supply capacity of fat. For a detailed introduction, please see the article “LSD Training Plan for Marathon Season”.
2) MAF training method
MAF, the maximum aerobic heart rate training method, is a running training method invented by Dr. Philip Maffetone, also known as MAF180. This method is relatively gentle and highly adaptable, and can be easily adapted to both professional athletes and amateurs.
MAF180 means subtracting age from 180 to calculate the maximum aerobic heart rate, and then adjust according to your own physical condition to determine the MAF heart rate zone.
The initial value of the MAF heart rate upper limit = 180 – age, and then adjusted according to the following conditions:
a. If you have a serious illness or have just recovered (heart disease, high blood pressure, just recovered from illness or just discharged from hospital), the upper limit of the heart rate is reduced by 10
b. Beginners who have never exercised before, who exercise intermittently, or who have more than two colds a year, or who have allergies, the upper limit of the heart rate will be reduced by 5
c. If you have exercised at least 4 times a week for more than two years, are not injured during exercise, and do not have the above symptoms. Increase heart rate limit by 5
MAF lower limit value = upper limit value minus 10
For example: For a 30-year-old person who does not usually exercise, the upper limit of MAF = 180-30-5 = 145, and the lower limit of MAF = 145-10 = 135. When performing MAF training, you can control the running speed to control the heart rate within the range of 135-145 beats/min, and close to 145 beats/min.
The characteristic of the MAF training method is that it focuses on heart rate and does not emphasize speed. When you first start training with MAF180, the speed may be very slow, but as the training continues and your cardiorespiratory endurance improves, the speed will continue to increase.
- Do strength training before running
Strength training can promote the secretion of adrenaline and norepinephrine in the body. Increased levels of these two hormones help accelerate fat decomposition.
The energy supply for strength training mainly comes from the anaerobic glycolysis of sugar. The product of this process is lactic acid. The accumulation of lactic acid will cause delayed muscle soreness. If strength training is followed by aerobic exercise, it can promote the decomposition and metabolism of lactic acid.
Strength training can build muscle. Increased muscle content will increase the level of basal metabolism. The increase in basal metabolic rate can increase the energy consumption of basal metabolism. In addition, equally important muscles are much smaller than fat. With increased muscle content, the body will be firmer and the body will look slimmer.
- Change evening running to morning running
After a night of energy consumption, the human body’s blood sugar level is relatively low in the morning. Starting to run in the morning can make fat become the main energy supply substance earlier. However, it should be noted that if you run in the morning on an empty stomach, avoid hypoglycemia. If you feel any discomfort, slow down or stop immediately and replenish energy.
- Increase “resistance” when running
You can increase the difficulty and energy consumption of running by running uphill. For hill running, you can choose a gentle slope. For people who use treadmills for running exercise, they can increase the slope of the treadmill without changing the running speed. In addition to increasing the intensity of exercise, increasing the slope of the treadmill can also reduce the stress on the tibial platform, thereby reducing knee joint injuries.
- Post-run stretching, relaxation and diet
Don’t stop exercising immediately after running. You should walk for a while and then stop completely to give your body enough time to cool down. After exercise stops, stretch and relax in time to avoid accumulation of fatigue. In addition, after exercise, you should consume more alkaline foods such as fruits and vegetables to speed up the body’s recovery from fatigue. Only when the body’s motivation is restored can it be better able to perform the next exercise.
