A marathon is a 26-mile running event often run on roads. As a marathon runner, your weight will significantly affect your speed and endurance. If you are in good physical shape, chances are you burn calories at a high enough rate to keep a suitable body weight for your height.
Effect of Weight on Speed
According to Dr. George Sheehan, a former general practitioner in New Jersey who wrote a column in Runner's World Magazine for 20 years, the weight-to-height ratio of a marathon runner is the key factor in terms of increasing his speed and time. This data reveals itself through past marathon winners as well as through the weight-to-height ratios of elite running athletes. Your weight should be 15 percent lighter than the average man at your same height. This high percentage decreases as the distance of your runs decreases. As a result, a sprinter only needs to be 2 1/2 percent lighter than the average person of the same height.
Losing Weight through Running
As you increase the amount of miles you log per week, you will burn calories, which should help you lose weight. In addition to running, eating foods that are low in fat, such as lean meat, fruit, vegetables and whole grains while avoiding fatty foods will help you lose weight at a faster pace. Running at about 80 percent of your maximum speed is the ideal rate for burning fat. Much like a car is most fuel efficient at a certain mph, your body maximizes fat burning at this speed.
In addition to losing weight to increase your marathon time, strength and additional cardiovascular training will help you increase your speed. While building muscle is counterproductive to marathon racing, keeping your muscles tight and toned will help keep you light and powerful while running. Performing barbell and dumbbell exercises with several repetitions and minimal weight will help you tone and carve your muscles. In addition, performing cardiovascular exercises such as swimming will help improve your lung capacity, allowing you to breathe more efficiently while running.
While running a marathon can keep you in peak physical condition, it is important that you consult with your doctor to ensure you are healthy enough to engage in such a rigorous race. In addition, burning calories and losing weight to improve your speed should be done with the help of a nutritionist or a health care specialist. Failure to do so might result in health complications or rapid weight lose that will decrease your overall stamina levels.