TheIntermittent Fitness Test is an Android app developed by Martin Buchheit, available for free download. The app is designed to help athletes with their high-intensity training by providing them with a unique test that measures their maximal aerobic power, anaerobic speed reserve, inter-effort recovery, and change of direction abilities. The test is widely used in almost every team and racquet sport of all playing standards across the globe.

The app is the first of its kind to provide field practitioners with written information on how to set up the test in the field and audio clues (sound files) for players to pace themselves throughout the test. The final speed of the test (VIFT) is a compound measure of the aforementioned abilities. When compared to continuous and/or linear tests, using VIFT allows for more homogenous metabolic responses during high-intensity training. With its simple design, the app is an excellent tool for athletes and coaches alike who want to improve their high-intensity training.