SUMMARY: Rugby-related TBIs are relatively rare events, yet the public’s perception of their actual risk may be greatly exaggerated. This mismatch could be explained by the feeling that partaking in volitional (such as sport) should be safer than non-volitional activities (e.g. driving one’s car). Nonetheless, TBIs should be reduced as much as practically possible to enhance the enjoyment of volitional activities.

PLEASE NOTE: This article does NOT consider concussions, which are a subset of mild Traumatic Brain Injuries (mTBIs)

This is a common misconception that contact or collision sports are the main cause of traumatic brain injuries (TBIs). This public misconception was highlighted recently in an article by a Sports Physician, Dr Bergeron, with over 20 years of clinical experience in the Pittsburgh Post-Gazette (Link to article). In this response to an earlier article in the same tabloid calling for an end to American Football, Dr Bergeron argues that general activities such as bike riding should be blamed long before ‘organised sport’ (such as rugby, cricket, soccer).

Moreover, evidence unequivocally shows that TBIs from recreational activities (organised sports and other activities such as bike riding) only account for approximately 10% (Bruns, 2003) of all brain injuries. Obviously, the majority of TBIs result from motor vehicle or ‘transport-related’ accidents. In South Africa for example, there are on average only two rugby-related traumatic brain injuries per year.

Of course travelling by car to work or school is not comparable to voluntarily partaking in an organised activity (such as rugby). However, research conducted on risk perceptions of soccer and rugby spectators indicates that what is considered ‘acceptable risk’ in these sports is not different to occupational levels (Fuller, 2008). This suggests that people consider the inherent of risks of sport to be comparable to those of everyday work-related activities.

So then why do organised sports have such a bad reputation for their association with brain injuries? The answer may lie in recent research on the Australian publics’ perception of shark attacks – an event that is as equally rare as rugby-related traumatic brain injuries (Crossley 2014). The Australia public’s fear of sustaining a shark attack was far greater than the true risk of such an event. The reason for this mismatch is complex, but related to the fact that humans’ emotions override logic when there is the possibility of any form of loss (unfortunately this is a loss of human life, in this context). Humans could also be more emotional about death resulting from volitional activities (swimming in the ocean or rugby) than driving one’s car to work because the volitional activities are done for enjoyment whereas driving one’s car could be seen as more of a necessity.

Nonetheless, if there is any possibility of reducing the risk of TBI, regardless of the activity, then these measures should obviously be employed. RugbySmart and BokSmart are two examples of prevention programmes that have the prevention of rugby-related TBIs as part of their mandate in New Zealand and South Africa, respectively. With on-going research, it is hoped that these programmes will be able to reduce the risk of these injuries as much as possible while still allowing the participants to enjoy the activities that they love.

What are your thoughts on this controversial topic of head injuries in sport? We’d like to hear them!

James

SUMMARY: LSD training is beneficial for team sports when utilised to build an aerobic base, but should not be implemented for prolonged periods of time. In intermittent high intensity team sports, interval training should be the primary form of conditioning prescribed

Here is a short summary of an article by Murach et al, published in the Strength & Conditioning Journal in 2013, entitled ‘Is long duration aerobic exercise necessary for anaerobic athletes?’

Pro Endurance Training

Endurance training has long been favoured over and above high intensity interval training to illicit aerobic physiological adaptations. Some of the known adaptations to aerobic or Long Slow Distance (LSD) type training include;

• Enhanced muscle blood supply through increased capitalization
• Increased mitochondrial density
• Fuel storage capacity (CHO sparing effect)
• Increased work capacity

Some strength and conditioning professionals around the world believe that too much endurance or LSD-based exercise is counterproductive for athletes competing in sports that are primarily anaerobic in nature (e.g. rugby, cricket, hockey etc.). These sentiments were brought to light many years ago during a study conducted on athletes performing aerobic and anaerobic training concurrently: in a study on [e.g. Rugby Union / League, Hockey, Cricket etc.] Hickson et al. [1980] found that this method of exercise prescription “blunted” strength gains. The authors of this study concluded that this “blunted” effect on [muscle strength and/or hypertrophy] was due to interference with the muscle’s physiological adaptations. However, some recent research has shown that concurrent training can be very beneficial if constructed correctly, highlighting the importance of Periodisation (a future post will focus more on concurrent training).

Con Endurance Training

As has been previously mentioned, LSD-type training is associated with many beneficial physiological adaptations. However, more recent, in-depth research has showed that High Intensity Interval Training (HIIT) can not only illicit the same adaptations to the aerobic energy system that LSD work does but also allows for adaptations to the anaerobic energy system. However, the inverse argument does not hold true: i.e. LSD training does not illicit beneficial adaptations to the anaerobic system.

Therefore HIIT has been shown to have the following physiological benefits;

• Increased maximal aerobic capacity
• Increased ventilatory threshold
• Increased acid buffering capacity
• Increased time to fatigue
• Increased Peak Power output (PPO)
• Increased substrate utilisation
• Increase Excess Post Exercise Oxygen Consumption

Practically, one of the main benefits of HIIT in comparison to LSD is that far less time is required to illicit these abovementioned benefits.

Other negative consequences of LSD include:

• Elevated cortisol levels due to high training loads
• Induced protein breakdown / catabolism
• Decrease rate of protein synthesis
• Inhibition of IGF-1 & testosterone

Conclusion:

LSD type exercise may be beneficial for anaerobic dominant sports when utilised in the correct manner (i.e. to build a base to allow for the implementation of HIIT at a later stage). This holds true for anyone training for weight loss, improved work capacity or training to improve the athlete’s threshold potential. However, if time is limited HIIT maybe the most beneficial to illicit both aerobic and anaerobic adaptations. Furthermore, LSD training significantly increase training loads in athletes participating in High Intensity Interval Sports, increasing the risk of overtraining. Lastly, the old saying of “if you train slow, you become slow” holds true. Thus, the implementation of HIIT, while manipulating rest periods is preferred for sports such as rugby, hockey and cricket to name a few.

Let us know your thoughts if you’d worked with a team and have tried various training modalities?

Wayne