This is a statement I have heard so many times, from women as well as men. I want to say the answer is simple, but it just isn’t that simple.
Your body needs to balance the food that you eat with the amount of energy you expend. The energy your body uses must be balanced with the nutrition you take in. If you are increasing your exercise regimen and not eating enough fuel to balance that energy, your body will think you are in ‘starvation mode’. If you are not eating enough food, your body will begin burning muscle rather than fat. That doesn’t sound like a good thing, does it?
In an effort to explain this further, I decided to look up some exercise/nutrition ratios on the internet and found this at http://www.livestrong.com:
“When you do exercise of any sort, you expend energy above and beyond what it takes for the normal operation of your body. You require energy to contract your muscles and to move your body mass around. When you do cardio exercise, you spend additional energy to increase your heart rate and respiration. Your heart and lungs play a crucial role during cardio exercise to mobilize and distribute the oxygen, hormones and enzymes your body uses to produce the energy your muscles need during exertion.
Cardio exercise, such as running, walking, skating, swimming and biking, involves repetitive exertion of your large, lower body muscles for a long enough period of time that your heart & respiration rates increase. Many experts, including MayoClinic.com, say you should do at least 30 minutes of cardio on a nearly daily basis to obtain health benefits. The American College of Sports Medicine advises 30 minutes of cardio activity at least five days a week, but notes that the activity can be broken into smaller sessions. The ACSM suggests that cardio activity should be maintained at least for 10 minutes during any given exercise period to obtain health and fitness benefits. However, technically, any amount of activity that elevates your respiration and heart rate will burn calories, including some fat calories. Experts recommend that you exercise for extended amounts of time because certain benefits accrue beyond the calories burned during the cardio workout.
Your car won’t move without gas to fuel its engine, and your body won’t run without energy to fuel its operations. Any activity you do burns calories.
Your body burns carbohydrates in the form of blood glucose for its usual activities. If you eat more calories than you can burn right at the time of ingestion, excess glucose is stored as glycogen in the muscles and the liver for later energy needs. As your glycogen stores fill, excess glucose is stored as triglycerides in fat cells distributed throughout your body under your skin and in your abdomen”.
By balancing your food intake and energy output, your body will work more efficiently.