A 35-year-old client wants to increase VO2 max by improving aerobic capacity and also reduce body fat over 12 weeks while maintaining muscle mass. Which program and nutrition pair is the best integrated plan?

• A. Program: Only heavy resistance training with short bursts of sprinting once monthly; Nutrition: extremely high-fat ketogenic diet with no carbohydrates during training days to force fat oxidation and maintain VO2 max improvements.
• B. Program: Daily static stretching sessions for flexibility and two low-intensity walks per week; Nutrition: very high carbohydrate intake (>70% calories) without caloric control to ensure energy availability.
• C. Program: Exclusively long slow distance cardio 6–7 days/week with no resistance training to maximize calorie burn; Nutrition: severe calorie restriction to accelerate fat loss and minimal protein since muscle preservation is secondary to rapid weight loss.
• D. Program: 3–4 sessions/week of interval and continuous aerobic training (including 1 high-intensity interval session and 2 moderate continuous sessions), plus 2 resistance sessions/week targeting major muscle groups, and daily dynamic stretching; Nutrition: modest calorie deficit (≈250–500 kcal/day), protein 1.6–1.8 g/kg/day to preserve muscle, and ensure adequate carbohydrate around workouts for performance and recovery.

Answer: (D)