The five components of physical fitness are cardiovascular endurance, muscular strength, muscular endurance, flexibility and body composition. Getting in shape means you should include exercises in your weekly routine that help you improve all components of physical fitness. Both running and sprinting can get you in better shape. Consult your health care professional before doing any new exercises.
Sprinting may be too intense if you have been inactive or if you have not run in some time. In fact, the best approach to getting in shape at the start of a new program is to begin by walking, then build up to a walk-and-jog routine, then increase the duration of your jog so that you are running non-stop for 30 minutes and finally incorporate sprint intervals. If you are already running, sprinting enhances your fitness, especially if you do a similar run multiple times per week. If you complete primarily sprint workouts, running non-stop for 30 or more minutes improves your cardiovascular endurance but decreases your sprint performance.
Risk of Injury
Sprinting has a higher risk of musculoskeletal injuries than running at lower intensities for a longer duration. If you have a lower-body joint problem, sprints might aggravate your condition. Your cardiovascular system must also work at a high capacity during sprints, so if you have cardiovascular disease, sprinting will not get you in better shape and might even be dangerous. It would be more harmful to you than a slower-paced jog, but always check with a doctor before doing any exercise.
Sprinting and running can both help you lose weight. If you only have 20 minutes, you burn more calories with a sprint-and-walk interval than with a 20-minute non-stop run. Sprinting incinerates more calories after the workout compared to steady running. Running for 45 minutes enhances your body's capacity to use fat as fuel instead of carbohydrates, improving your fat-burning capacity. By incorporating both types of training protocols, you improve your cardiovascular fitness and your body composition, getting in better shape.
Anaerobic Vs. Aerobic
Anaerobic metabolism, or the conversion of the food you eat to energy your cells can use without oxygen, precedes aerobic metabolism, which uses oxygen to make energy. Anaerobic metabolism occurs rapidly, as in sprinting, while the by-products of anaerobic metabolism are used in aerobic metabolism, as in running, if you continue to run. When you first start running, your body produces energy from anaerobic metabolism. As you continue to run past 3 minutes, your body makes energy from primarily aerobic metabolism. If you sprint for 30 seconds then walk, your sprints are fueled by anaerobic metabolism. An enhanced anaerobic system augments your aerobic system, improving your fitness.
Middle-distance runners aiming to improve performance can benefit from a sprint workout included in their conditioning programs. Sprint intervals increase the point at which a runner experiences muscle fatigue from lactic acid buildup, an excellent adaptation for sprinters and runners. This means if you run 5-kilometer races and you incorporate sprint training once per week or every other week, you can run at a faster pace for a longer duration, beating your personal time and getting in better shape.
Sprinters, however, should not be running a continuous 3 miles in their conditioning programs because the metabolic changes in muscle cells to run nonstop are not beneficial for short, intense training. In fact, if you are a sprinter and incorporate a long run every week or every other week, your performance decreases.
- Strength and Conditioning Journal; High-Intensity Interval Training: Applications for General Fitness Training; Brad Schoenfeld, et al.
- Strength and Conditioning Journal; Fat Burning; Bruce Craig, Ph.D.
- Exercise Physiology, Energy, Nutrition & Human Performance; William McArdle, et al.
- Essentials of Strength Training and Conditioning; Thomas R. Baechl, et al.