CrossFit is a popular high intensity training program combining weightlifting, gymnastics and aerobic training. Concerns about high intensity conditioning such as CrossFit involve the perception that there is an increased risk of musculoskeletal injury from these demanding programs. A recent review in the Journal of Sport Rehabilitation reported that incidences of injuries associated with CrossFit training programs were comparable or lower than rates of injury in Olympic weightlifting, distance running, track and field, rugby, or gymnastics.

Acute injuries

Whilst acute injuries do occur in CrossFit, particularly at the elite level during competition, as with any other sport, chronic, insidious overuse injuries are far more common, especially in people who use CrossFit as a recreational training method rather than a competitive sport.

Studies looking at injury patterns among CrossFit athletes have found the most common lower body part injured in CrossFit is the knee.

Knee injuries can be acute, particularly during weight lifting disciplines at competition level, however most knee pain that develops during CrossFit participation is anterior knee pain secondary to overuse injury.

Overuse injuries

Overuse injuries often stem from a dysfunction within the kinetic chain and management needs to address all possible deficiencies in the chain, not just the area of pain. Knee pain may be related to weak gluteal muscles, tight hip flexors and other muscles around the hip joint, unfavorable ankle biomechanics and foot posture and/or poor core stability.

The important thing to note is that any CrossFit enthusiast presenting with pain during movement does need to have their injury assessed and managed but concurrently there are still many things they will be able to continue to do in the meantime, so that they can still fulfill their activity goals whilst addressing their problem.

Avoidance of aggravating activities in the short term and assessment by a physiotherapist or Sport and Exercise Physician, ideally one familiar with CrossFit, for a structured rehabilitation program with targeted soft tissue strengthening and stretching are warranted for any pain lasting longer than 1-2 weeks.

Knee pain case study

  • A recreational CrossFitter who participates in 6 CrossFit classes per week including 2 weight lifting specific classes presents with knee pain during squatting
  • A thorough history and examination is performed to assess for common causes of knee pain such as meniscal tear, ligament injury, patella tendinopathy or osteoarthritis (see knee injuries for more details on these conditions)
  • Further investigations such as x-rays or MRI may be indicated to rule in or out specific structural pathology after considering the clinical information from the history and physical examination but are not always needed
  • Often a clearly identified injured structure is NOT found in people presenting with pain during CrossFit movements (which is a good thing), but this is also when many are mistakenly told to rest until the pain goes away
  • The problem with resting to fix a pain is that it never really goes away and when the person returns to the same activity that caused their pain, the pain returns too
  • In order for something to change, you need to change something!
  • Specific to the knee, factors such as patellar malalignment, quadriceps muscle weakness or imbalance, gluteal weakness, poor ankle range of motion and faulty foot biomechanics may play a contributing role
  • Unfortunately many athletes don’t present in the initial stages of injury, instead they continue to train with avoidance of the few movements that cause them pain – the problem with this is that it often reinforces the strength and length imbalances in their kinetic chain, so although it relieves pain in the short term, it can actually make the problem worse in the long term
  • For most lower limb injuries, the answer isn’t to stop training legs completely, but instead to do specific leg training that leads to strengthening of weak muscles and lengthening of short muscles so that the problem can be reversed, followed by a gradual reintroduction of all lower limb movements as appropriate to the individual
  • The art in managing most overuse conditions is to work out what muscles are weak and need strengthening, which ones are short and need lengthening and what rehabilitation exercises are needed initially to re-establish correct neuromuscular activation and coordinated movement patterns
  • In regards to the knee, the work often starts at the hip and the exercises need to be in functional positions – there is no point training the gluteal muscles to activate in a lying position and then expecting them to turn on when squatting
  • The most important part of any rehabilitation program is to have movement specific, functional exercises to encourage correct neuromotor patterning – often the muscle isn’t particularly weak, it’s just not being recruited or turned on by the brain during the movement
  • Rehabilitation is just as much about training the brain as it is about training the muscles – full attention is needed and movements must be performed correctly – the focus should be on proper form not on counting reps and the athlete should stop when fatigue hits and good form is lost
  • Management of overuse injuries in this way requires skill from the assessor and diligence from the athlete but the athlete should be able to return to full pain free movements if they put the work in and are guided through a graduated and progressive, CrossFit specific rehabilitation program – at the end of the day, exercise is medicine!