High Intensity Training (HIT) is a special kind of short and intense weight training that focuses on using maximum muscle power for a brief time. This makes the muscles tired quickly. Because it’s so intense, HIT requires more time for the body to recover compared to other weight training methods. HIT became popular among bodybuilders in the 1970s as a different way to train muscles, with shorter but more challenging exercises than traditional weight training that uses more repetitions and sets.
HIT programs usually involve doing one set of exercises for each muscle group, 2 to 3 times a week. The exercises involve slow and controlled movements lasting around 30 seconds per repetition. The goal is to make the muscles very tired after one session, so the program may include static holding and eccentric muscle contractions to achieve this. The main results of HIT are increased power and strength (Kraemer et al., 1995).
Another term, High-Intensity Low-Volume Interval Training (HIIT), is a form of endurance training that alternates between intense bursts of activity and periods of lower-intensity activity. HIIT aims to extend the time of high-intensity exercise to improve overall performance, such as increasing oxygen uptake (Gormley et al., 2008; McKay et al., 2009; Sperlich et al., 2010; Tabata et al., 1996). It can be done in a shorter time (Gibala et al., 2006) compared to moderate-intensity continuous training (MICT), making it popular among different athletes and those seeking to improve their endurance quickly. However, research does suggest that mild intensity cardiovascular training is recommended as a precursor for successful use of HIIT (Stoggl & Sperlich, 2014).
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Sperlich, B., Zinner, C., Heilemann, I., Kjendlie, P. L., Holmberg, H. C., & Mester, J. (2010). High-intensity inter- val training improves VO(2peak), maximal lactate accumulation, time trial and competition performance in 9-11-year- old swimmers. European Journal of Applied Physiology, 110(5), 1029 1036. Available from https://doi.org/10.1007/ s00421-010-1586-4.
Stoggl, T., & Sperlich, B. (2014). Polarized training has greater impact on key endurance variables than threshold, high intensity, or high volume training. Frontiers in Physiology, 5, 33. Available from https://doi.org/10.3389/ fphys.2014.00033.
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