Mark York and Whitney Sullivan trim and tone physiques at their company PNF, which stands for Personalized Nutrition and Fitness. They don’t take a one-size-fits-all approach to creating any fitness regimen or meal plan. Instead, they combine the focused exercise of personal training with the crowd motivation of group-fitness classes. Their classes range from familiar standbys like yoga and kickboxing to cheekily titled circuit-training classes such as “buns and guns.” They supplement these sweat sessions with custom nutritional counseling, which, depending on your fitness aspirations, could include guidance on how to make vegetarian recipes, design more energy-packed meals, or stop compulsively eating staples at your desk.