Energy Balance

Kathy will keep a negative energy balance until she reaches her ultimate weight goal of around 152 pounds. Her initial goal will be to decrease her weight by 5 to 7 percent (about 10 pounds) by working up to losing approximately 1 pound per week. As discussed in an earlier chapter, 1 pound is approximately 3,500 calories. So Kathy needs to create a negative energy balance of 3,500. Let's calculate how much exercise she will have to do to create a negative energy balance of 3,500 calories per week, assuming that her 1,700-calorie diet without exercise would put her in a neutral energy balance (keeping her weight stable).

Weekly caloric goal is 3,500 calories per week.

Body weight is 192 pounds (87.1 kilograms).

MET level is 6 (walking).

Calculation: To meet her goal, Kathy will need to burn 9.14 calories per minute to meet her goal; the calculation is ( 6 X 3.5 X 87.1 )/ 200 = 9.14. And 3,500 calories per week divided by 9.14 calories per minute gives her the number of minutes she needs to exercise per week, which is 382. To find out the number of minutes per day, she needs to take the number of days per week that she plans on exercising, which is 4 to 7. So we take 382 minutes per week and divide it by the number of days per week of exercise sessions. To meet her weight-loss goal (negative calorie balance), she will need to work her way up to walking 96 minutes (1 hour, 36 minutes) per day, 4 days a week or 55 minutes per day, 7 days a week. When she reaches the point when she is able to do more intense exercising, such as running, she will have shorter durations of exercise that will help her meet her goal. She will also burn more calories as she starts to do strengthening exercises, which can also be calculated by using the MET units for those types of activities. In addition, she can decrease her caloric intake by 250 calories and cut her exercise in half to achieve the same weight-loss goal. You can experiment with these types of calculations for different types of exercise and caloric intakes.

An action plan can include whatever type of exercise you enjoy or have available. Many options exist, such as cycling classes at a local fitness facility.

Remember that you do not have to do as much exercise as shown in Kathy's plan to see a positive change in your health. Also recognize that as her exercise level increases, she will have to increase her caloric intake for her weight-loss rate to remain stable. If she did not increase her food intake, her weight-loss rate would increase, and vice versa in accordance with the principle of energy balance. Finding this balance is the challenge here. This is where keeping your action plan log book up to date can be helpful to you. Charting your meals, your exercise, and your response (weight and glucose level changes) will allow you to see positive and negative trends in your plan.