EVIDENCE-BASED PRACTICE :
INSTABILITY TRAINING
Proponents of training on unstable surfaces argue that it can increase muscle activation , improve proprioception and balance , and improve neuromuscular control . What does the research say ?
WORDS : DR MARK MCKEAN PhD
T he fitness industry is very good at
embracing new methods and ideas related to training styles and exercise options . Over the last decade there has been a real shift from traditional methods of training , inclusive of resistance training , to a variety of methods that are considered more ‘ functional ’ or even more ‘ holistic ’ in their nature .
Activities that include a balance or stability component have become commonplace , with some ‘ developing ’ to the point where they are bordering on dangerous . Instability training has many aspects , but broadly describes activities in which the individual is required to maintain control over their body position while it is being challenged by a destabilising device or technique .
The definition of ‘ instability ’ is a loss of stiffness , and joint instability is a lack of support or control of joints , which puts the individual at risk of joint displacement or dislocation .
Several arguments have been put forward in support of exercising on a surface that is less than stable . These include increased muscle activation , improved proprioception , better neuromuscular control and improved balance coordination . Let ’ s look at some key points that research has definitively shown to be true about some of these arguments .
Key Point 1 : Balance training does not transfer to different tasks
In a major systematic review and meta-analysis paper published in March 2016 , Kummel et al . conclude that balance training will only improve the performance of the balance tasks being trained . The transfer of these improvements to different tasks was very small or non-existent . Even when the task involved a similar body position or similar balance demands , the transfer did not occur in any substantial manner . Giboin et al ( 2015 ) found likewise , stating that even when the device and direction of change was similar , there was little transfer of performance between tasks .
Balance board training has been shown to reduce injury risk , but only when the participant has had a previous similar injury , with Peterson et al . ( 2013 ) finding that proprioception training of the ankle reduces risk of another ankle sprain . An important side note here is that the sensory feedback loop for an automatic postural adjustment is approximately 70-120 ms and the functional response is 120-180 ms . Injuries such as ankle sprain occur in a timeframe of 40-50
The 30-second article
• Research has found little transference of balance training skills between tasks
• Balance training does appear to assist the elderly in reducing the risk of falls
• Research found that while the challenges to postural stability may be greater during training on an unstable surface , this increased degree of stress does not lead to improved balance
• To increase strength , power and hypertrophy , it is more valuable to exercise on a stable surface .
56 | NETWORK SPRING 2016