Although 10 pounds might sound like a lot of weight to lose, it doesn't have to take long to reach your goal. Deceptively easy-fixes, such as crash diets, aren't safe and the weight you lose, which is often lean muscle and water weight, is quickly gained back. MayoClinic.com recommends losing the weight and keeping it off by creating a gradual weight-loss rate of no more than two pounds per week.
Calculate Your Calories
One pound of fat has 3,500 calories. This means, that to lose 10 pounds in 40 days, you must create a daily deficit of 875 calories so you lose a little less than two pounds per week. You can create this deficit by making dietary changes so you consume fewer calories, and you can perform regular exercise to burn extra calories. Although it's easier to cut calories from food, including exercise in your weight-loss regimen, and continuing it after you've reached your goal, can help you maintain your results.
Makeover Your Diet
Before starting your weight-loss journey, keep track of how many calories you eat on a daily basis. Then start gradually making changes. Skip fattening desserts, morning doughnuts, sugary sodas and late-night chips -- replace them with healthier fare, such as fruits, veggies, water and air-popped popcorn. Include lean protein, such as tuna in water, turkey, salmon and skinless chicken. Compare food labels to make healthy choices that won't sabotage your weight loss. Eating smaller portions can also help reduce your caloric intake, especially if you're dining out.
Cardio Burns Calories
Cardio can burn calories that contribute to weight loss. MayoClinic.com recommends doing 150 to 300 minutes per week. Find activities that you enjoy doing so you can do them throughout and after the 40 days. An hour of walking at a pace of 2 mph, for instance, burns 255 calories in a person who weighs 200 pounds, while swimming laps and a game of racquetball over the same duration, can burn more than 500 calories. You can split exercise up into three sessions over the day to get in your daily requirement.
Muscle Boosts Your Metabolism
As you lose weight, strength training can prevent the loss of muscle tissue, and help to increase it. According to Franklin & Marshall College, three 25-minute strength-training sessions per week can make you gain three pounds of muscle in about eight weeks and increase your resting metabolism by 7 percent. Use your bodyweight, weightlifting machines, free weights or exercise bands for resistance -- and if you're new to strength training, learn proper form to prevent injuries and optimize results.