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Sports injury prevention for all athletes
—Correct Knowledge and Methods—

Norikazu Hirose
Associate Professor, of Sport Sciences, Waseda University

Do you enjoy playing sport? Typically people start exercising at this time of year trying to make up for overstuffing themselves during the holiday season. The most important thing when we are trying to improve our athletic skills or lose weight is to keep exercising consistently. One of the things that stop us from keeping up with exercise is injury. Below I will be introducing some of the global consensus and the latest knowledge and methods for preventing injuries during sporting activity.

Moving from “fast recovery” towards “preventing injury”—global initiatives in sporting injury prevention—

Injuries suffered in sports are referred to as “sports injuries” and can be classified into two types: acute injury and chronic injury. Acute injury is caused by a sudden strong stress, such as a sprain, and chronic injuries is caused by repetitive small stress on the same part of the body, such as knee pain (Jumper’s knee). It is important to prevent both types of sporting injuries because they both stop people from playing sport and exercises.

In recent years, sports injury prevention has attracted attention at a global level. International Olympic Committee (IOC) hosts a World Conference regularly on the theme of preventing injuries.

The importance of preventing injuries is widely known, and preventive methods have been developed based on scientific evidence1, but the appropriate methods are not implemented in clinical settings. So what is our strategy to prevent sports injuries would be?

Moving from “warming up” to “preparing”—prehabilitation as an injury prevention method—

In recent years, preparing the body before exercises has been recognized as an important principle and widely practiced in athletic settings as a part of conditioning to prevent sports injuries. The key is to “prepare” the body and not just “warm up” during pre-exercise warming up. It has been reported that continuous use of exercises program that promote functional use of the body, instead of general warming up such as jogging, can prevent nearly 50% of severe acute injury and chronic injuries in young athletes and female athletes 1. This form of exercise program is referred to as prehabilitation2.

I promote the following six elements of functional exercises as prehabilitation for the prevention of sports injuries from the torso through to the legs2. However, these exercises must be performed correctly. Why do we need to select these six elements and implement them correctly?

(1) Whole body coordination (2) Mobility (3) Muscle function
(4) Balance (5) Optimized movement (6) Plyometrics

* The key is to concentrate on preparing the trunk muscles when perform these six exercises!

Methods for preventing injuries by analyzing mechanism of injuries—the “how” and the “why”—

When developing prehabilitation, the first thing we need to consider is how and why the injuries occur. Let’s use ankle sprain as an example (Figure 1). Most of ankle sprains are caused by twisting the ankle inwards at the moment of landing or turning. In other words, if the ankle is kept stabilized during exercise there will be no sprain! This is an improvement that can be achieved by thinking about “how” an injury occurs.

So why do ankles twist inwards? A variety of causes become apparent when we analyze the “why”. Possible reasons include faulty function of the muscles that move the ankle outwards (peroneal muscles), or it could be impaired balance ability. Sometimes ankle sprains occur because of incorrect use of the buttock muscles (gluteus medius, etc.) or trunk muscles (core muscle group), which are located far from the ankle. It is possible to stop inward twisting of the ankle and prevent sprains by improving these areas! This is a way of correcting the “why” of sports injuries.

In other words, the key to prehabilitation is to carry out exercises that achieve improvements in “why” injuries occur, while being aware of “how” to move without suffering injuries. There are some small differences between the exercises that people need to do in order to prevent injuries, depending on the individual characteristics. The prehabilitation described above is largely aimed at preventing ankle and knee sprains, and it will improve the “why” of sports injuries for the most of cases. I am sure you can now see why “warming up” is not enough by itself.

Cooperating with experts to find the right exercises for you—discussion between athletes and experts—

As described above, preventing sports injuries is not hard if you have the correct knowledge and methods. However, if you look at the fact that more than 90% of athletes (volleyball players) have experienced ankle sprains3, it is clear that proper preparation is not always carried out. In order to improve this situation, the first thing we need to do is ensure that athletes and coaches both acquire the correct knowledge and methods.

It is also important for individuals and experts to work together to come up with exercises that suit the individual. The “how” of ankle sprains described above is the same for everyone, irrespective of age or gender. However, the “why” differs between individuals (Table 1). Ignoring this fact and just going through the exercises based on the latest “theories” or “methods” will not necessarily produce positive results. Thus, it is important to learn “why” you suffer injuries by studying from books or speaking to experts, and to work with experts to develop methods to improve your “why”. Experts such as athletics coaches can be found at local fitness clubs, clinics, and treatment centers. Let’s work together to learn the correct knowledge and methods for us as individuals and help to develop healthy body and mind as well as a healthy society through sport.

Table 1: Causes and elements to target when carrying out conditioning and preventing injury

Main factors Elements Examples of elements
Internal factors - Physical  
Form Physique Weight, body fat, atrophy, different leg length
Alignment Posture, static alignment
Function Joint function Range of motion, laxity
Muscle function Muscular strength and endurance, tightness
Nervous system function Cognition and decision, reaction, balance
Cardiorespiratory function Aerobic endurance, anaerobic endurance
- Skill Technique, dynamic alignment
- Mental Tension, motivation
- Medical Medical history, current illness
External factors - Environment Surface, weather
- Equipment Shoes, protective equipment, accessories
- Training Volume, intensity, quality and timing of training
Warming up/cooling down

I am particularly grateful for the assistance given by Kaori Okamoto, Athletic Training Fellow of Stanford University.

1) Soligard T, et al. (2008). “Comprehensive warm-up programme to prevent injuries in young female footballers: cluster randomised controlled trial.” BMJ, 1-9. (PDF can be downloaded from http://www.bmj.com/content/337/bmj.a2469.pdf%2Bhtml).
2) Norikazu Hirose (2013). “Prehabilitation” Coaching Clinic for Preventing Injuries [Shogai Yobo no tame no Purihabiriteshon].”Coaching Clinic 2013 (7), 64-67.
3) Ikuhiro Morikita (2000). “Injuries in Top-level Volleyball Players: Results from a Questionnaire Survey.” Japanese Journal of Orthopaedic Sports Medicine 20 (1), 18-21.

Note 1: One example of this is the FIFA11+ program promoted by FIFA. An introduction of the exercises written in Japanese can be downloaded from the medical section of the Japan Football Association website. The URL is as follows: http://www.jfa.jp/football_family/medical/11plus.html
Note 2: The word prehabilitation was coined by combining “pre” with “habilitation” (which derives from the Latin word habilis, meaning capable or suitable). In other words, prehabilitation means preparing the body in advance so that it can be used properly.

Norikazu Hirose
Associate Professor, Faculty of Sport Sciences, Waseda University; Physical Coach for Japan’s National Women’s Soccer Team; Conditioning Coach for JEF United Ichihara Chiba Youth Academy

After graduating in Sports Sciences from the Faculty of Human Science, Waseda University, Professor Hirose joined the Graduate School of Arts and Sciences, The University of Tokyo and completed a Ph. D. there. Specialist fields include athletic training, growth and development.
He has worked as a physical coach for junior and youth soccer players at clubs including Verdy Kawasaki (currently Tokyo Verdy), Nagoya Grampus, Kyoto Sanga and JEF United Ichihara Chiba. Since 2008, he has supported female soccer players, working as a physical coach for Japan’s national women’s soccer team.
Recent books include “Core training for women: How to Improve Muscular Function for a Beautiful Body [Joshi no Taikan Ressun: Utsukushii Karada ni naru Kinniku no Tsukekata] (Gakken Publishing).
He also plans to publish the following book in the near future: Non-Muscular Training for Building Toughness—Functional Exercise Improves“Body Coordination” [Tsukarenikui Karada o Tsukuru Hi-Kinniku Toreningu] (Kadokawa Shoten).