CrossFit vs high intensity interval training

Posted on 12 January 2017

While CrossFit and high intensity interval training (HIIT) share some similarities, they are two distinct training methods. Our biokinetics expert explains how each works and weighs up the pros and cons.

With innovation dominating our daily lives, many a trend or modification is built on already tried and tested principles. The fitness world is no different, and two specialised training techniques are as popular as they are demanding.

CrossFit and high intensity interval training are well-known fitness modalities. And while both involve a high level of exertion, they differ in many respects.

‘CrossFit involves a wide range of functional movement focusing on strength and conditioning,’ explains Kimberley-based biokineticist Ansoné Hugo. ‘It takes selected aspects of gymnastics, weightlifting and running and mixes them into one long workout. High intensity interval training alternates between short intense efforts and longer rest periods, where the athlete recovers sufficiently before the next burst. The overall workout is much shorter and the training effect leans more towards athletic conditioning.’


CrossFit involves some degree of HIIT in terms of sprinting and working towards maximum anaerobic efforts. Similarly, HIIT can also involve weightlifting, so there is some overlap. But the duration, structure and even training venues used are markedly different, Ansoné explains.

‘CrossFit is more structured and is performed in a gym,’ she says. ‘The sessions are group-orientated, often under supervision, and last anywhere between 45 minutes to an hour. A variety of exercises are involved and very few – if any – rest intervals are taken.’

‘HIIT is more individual,’ she continues. ‘It can be done anytime or anywhere and includes rest intervals between all-out efforts. The length of these recovery periods vary according to fitness levels, allowing the body to build lean muscle mass by tapping into the phosphagen system.’ This system uses creatine phosphate in the body and is employed when there is a sudden increase in energy demand. In short, creatine phosphate is a molecule that serves as a rapid release reserve of high-energy.

Typical workouts

Ansoné offers the following workout examples:

  • CrossFit: ‘An intense combination of pull-ups, weighted push-ups, squats and sprints for 30 minutes followed by the workout of the day (WOD). This typically involves as many repetitions of burpees, push-ups and sprints as possible in 10 minutes.’
  • HIIT: ‘Jog around a soccer field to warm up and transition into 6 x 80-metre sprints with around 60 seconds of walking recovery between each. Walk-jog back around the field to cool down.’


While CrossFit and HIIT have their respective benefits, Ansoné emphasises a healthy and sensible approach to both training methods.

‘It is very easy to overdo things, especially for highly motivated people,’ she cautions. ‘HIIT is very taxing on the anaerobic system [which functions by glycolysis, the breakdown of glucose]. It is important that the prescribed recovery intervals are taken. Muscular injuries and illness are the most common ailments if an HIIT athlete over-trains.’

‘CrossFit is far more ballistic and weight-bearing,’ Ansoné adds. ‘Participants are prone to Achilles tendon strains and rotator cuff injuries. Proper technique is everything, so it is preferable to have proper coaching and instruction when attempting the various exercises, especially when it comes to heavy weightlifting. Overtraining can also lead to muscle breakdown, which can increase the risk of kidney failure.’

Published in Exercise

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