High knees is a vigorous, plyometric exercise that falls under the category of high-intensity cardiovascular training. The movement involves rapidly bringing the knees up toward the chest, engaging the core and large muscle groups of the lower body. This exercise is frequently performed as part of high-intensity interval training (HIIT) to elevate the heart rate quickly. Many exercisers question whether this movement can directly influence the reduction of fat located in the abdominal area.
The Myth of Targeted Fat Loss
The idea that performing an exercise for a specific body part will cause fat loss in that exact area is a concept known as “spot reduction.” Scientific evidence, however, consistently shows that this type of targeted fat loss is not physiologically possible. When the body needs energy, it mobilizes fat stores from across the entire body, not just the muscles being worked.
Fat is stored within cells as triglycerides, which are large molecules that muscle cells cannot use directly for fuel. Before being used for energy, the triglycerides must first be broken down into glycerol and free fatty acids through a process called lipolysis. These smaller components are then released into the bloodstream and circulated throughout the body to be used by working muscles.
Because the fat released into the bloodstream can originate from any fat reserve in the body, where an individual loses fat first is largely determined by genetics, hormones, and overall body fat percentage. While high knees will strengthen the abdominal muscles used to lift the legs, this action alone does not signal the body to exclusively burn fat from the belly. Therefore, high knees cannot specifically target and burn belly fat.
How High Knees Supports Calorie Expenditure
Although high knees cannot target abdominal fat, they are an effective tool for creating the caloric deficit necessary for overall fat reduction. This high-intensity activity engages multiple large muscle groups simultaneously, including the quadriceps, hamstrings, glutes, and hip flexors. This full-body engagement dramatically increases the heart rate and oxygen consumption, leading to a high expenditure of calories in a short amount of time.
The intensity of high knees makes them suitable for High-Intensity Interval Training (HIIT), which maximizes energy output. High-intensity exercise is effective at triggering Excess Post-exercise Oxygen Consumption (EPOC), often called the “afterburn effect.” EPOC is the elevated rate of oxygen intake and calorie burning that continues after the workout has ended as the body restores itself to a resting state.
This post-exercise energy expenditure significantly contributes to an individual’s total daily calorie burn. Research suggests the EPOC effect can increase overall calorie consumption by an additional 6% to 15% of the calories burned during the session. By consistently creating this large energy deficit, high knees supports systemic fat loss that will eventually include fat deposits from the abdominal region.
Comprehensive Strategy for Reducing Visceral Fat
To effectively reduce belly fat, particularly the more concerning visceral fat that surrounds internal organs, a comprehensive approach is required. Visceral fat is highly responsive to lifestyle changes and its reduction is primarily driven by achieving a consistent caloric deficit. While high knees support this deficit, the most impactful change comes from adjusting nutrition.
Reducing the intake of refined sugars and processed carbohydrates is effective, as these foods can promote the storage of visceral fat. Prioritizing a diet rich in protein and soluble fiber helps increase satiety and control appetite, aiding in managing calorie intake. Lean protein and fiber-rich vegetables, fruits, and whole grains should form the foundation of a fat-loss eating plan.
A complete exercise regimen should combine vigorous cardio, like high knees, with regular resistance training. Building lean muscle mass increases the body’s resting metabolic rate, meaning more calories are burned even when the body is at rest. This combined approach accelerates the overall fat-loss process, improving body composition more effectively than cardio alone.
Beyond diet and exercise, managing lifestyle factors influences the reduction of abdominal fat. Chronic stress elevates the hormone cortisol, which is directly linked to increased visceral fat storage. Consistently getting seven to eight hours of quality sleep helps regulate hunger hormones and minimizes the stress response, supporting the body’s ability to mobilize and burn fat.