Sit-ups remain one of the best methods of reshaping the abdomen, second only to standing in front of a lit cannon. Enjoy explosive exercise with today’s Groupon: for $49, you get a three-week fitness-and-nutrition package from Reshape Boot Camp (a $485 total value). The package includes the following:

• Three weeks of unlimited boot-camp classes (a $336 value). Classes are held at Tumble Bugs Gymnasium in Riverside through April 6 and at Roger Sherman Baldwin Park in Greenwich beginning April 7. Classes take place at the following times:
• Mondays at 5:30 a.m., 6:15 a.m. and 7 p.m.
• Wednesdays at 5:30 a.m. and 7 p.m.
• Thursdays at 5:30 a.m., 6:15 a.m.
• Saturdays at 7:45 a.m.<p>
• A 21-day eating plan (a $149 value), which includes the following:
• A three-day detox menu
• Three weeks of meal plans and grocery lists
• Recipes and food-swap ideas
• A goal-setting journal<p>

A certified personal trainer who won his own struggle with childhood obesity, Patrick Jones sculpts svelte physiques with modifiable exercises in indoor and outdoor boot camps. Held four times a week, Patrick’s 45-minute classes take calories to task with intense strength-training and aerobic exercises. Push-ups and lunges tone sinews in the limbs and core, and hungry cheetahs chase students across open fields in sprinting drills that cultivate speed and stamina. A recent graduate of Kai Yoga’s teacher-training program, Patrick may draw on his knowledge to incorporate poses that refine focus, flexibility, and levitation techniques.

As a licensed sports nutritionist, Patrick also guides students toward healthy eating habits that complement their workout regimens. To bolster weight-loss goals, today’s Groupon includes three weeks of meal plans, a collection of nutritious recipes, and a journal for working through crushes on calorie-packed gingerbread men.