Studies show that when done correctly, high intensity interval training (HIIT) and cross training have many health benefits. They build stamina, melt calories and fat more efficiently than do other forms of exercise, enhance motivation, prevent overuse injuries and boredom, and create muscular strength and balance across all areas of the body. To become stronger and to perform at their best, our muscles need to be stimulated in various ways. Working and excelling at one form of exercise such as running or weight lifting does not mean that we are fit. All we need to do is get on a tennis court to figure this out—huff, puff, sweat, burn out in just a few minutes! Being in good shape means being able to do many types of exercise as well as everyday activities (i.e. picking up a child) without quickly fatiguing or risking injury. According to WebMD, “Athletic trainers and personal coaches agree it's cross training -- essentially, alternating your workout routines in a way that will increase your performance and overall fitness without stressing your body to the max,” that makes a fit person. I specifically designed JWM fitness workouts to include both HIIT routines--total body calisthenics plus plyometrics in rapid succession--and cross training sports cardio sessions--running, spinning, rowing, elliptical, swimming, hiking...etc. The workouts alternate day-to-day and also include weight training and stretching through yoga poses. Watch and try to perform (if you are healthy and/or have consulted your doctor) a FREE JWM high intensity aerobic workout by clicking here. Then, click on the box appropriate for your level--Level 1, Level 2, or Specialty--and select one of the following videos: Level 1 30-Minute Workout Level 2 30-Minute Workout Specialty 30-Minute Workout Please note: If you are not use to doing HIIT, you might find the above routines difficult at first. Take short breaks if you need to catch your breath (30 seconds). If you are starting your fitness program from scratch, it is best to begin by building your sports cardio endurance before you move to HIIT and cross training. I provide sports cardio guidance in the JWM daily calendars available to subscribers. The complete JWM fitness programs with over 150 exercises modules for toning and cardio are one click away. Get fit now here! Click here to read more about the benefits of cross trainings in The New York Times.