From HIIT and CrossFit to spinning and functional training, here are four good reasons to jump onboard the latest trend for high-intensity interval-based workouts that combine short, intense bursts of activity with low-intensity active recovery.

Get great results, fast!

Military-inspired interval training sessions, combining short 30-second bursts of intense activity with short recovery periods, can change the shape of your body in record time by burning fat.

CrossFit combines elements of weight lifting (lifting, throwing, moving objects), classic gym exercises (push-ups, pull-ups, rings) and cardio training (running, rowing, cycling).

Some HIIT (High Intensity Interval Training) programmes use body weight rather than equipment, boosting metabolism with a workout based on a series of standard exercises (squats, wall sits, lunges, planks, jumps, etc.) that work all muscle groups. This type of exercise can burn up to 800 calories in 30 minutes.

Circuit-based functional training programmes are also popular at the moment.

Slow down aging

A study, published March 7 in Cell Metabolism, found that using HIIT training techniques in aerobic, endurance-based activities like cycling and walking could slow down ageing at cellular level. This involves adding short bursts of higher-intensity activity to a regular workout, like a 30-second sprint in the middle of a slower-paced jog, for example. This was found to boost the action of cell powerhouses called mitochondria, whose ability to generate energy declines with age.

Save time

These short but intense exercise sessions can fit easily into busy daily schedules. High Intensity Interval Training or functional training sessions usually last around 30 minutes. CrossFit sessions usually last up to an hour and high-intensity spin classes are 45 to 60 minutes in length. Classes can now be booked online at a growing number of gyms, making last-minute sessions more feasible.

Get tips and motivation from a coach

In this type of class, there’s usually at least one coach for around 12 participants. The trainer sets the programme of exercises for each session with a “workout of the day.” They are also on hand to offer personalized tips and advice tailored to individual levels or goals. Exercising in a group can also prove more motivating than slogging it out alone with a screen on an MP3 for company.