Endurance sport is one of the greatest tests of mental and physical toughness. During a marathon an athlete, on average, will complete 160-200 steps per minute. Whilst running has numerous benefits for our health and wellbeing, it can be monotonous loading on the skeletal system. Bony stress injuries account for up to 20% of running related injuries per year. It is believed that one reason for this is the repetitive overloading on runners’ bones. In comparison, activities involving irregular movements seem to foster greater bone health. The ultimate goal should always be injury prevention, so, should runners incorporate directional movements into their training repertoire for bone health?
Bone is an alive, adaptable, and dynamic structure. Our bone density increases as we grow and by 30 our density is at its peak. After this age we can only maintain what we have. Bone health refers to our bones’ mineral density and quality and is the result of a plethora of factors. In otherwise healthy runners, energy availability, biomechanics, training load and recovery, all play important roles in creating good bone health. Poor bone health can increase the risk of fractures during one’s developmental years and later in life.
There are two main theories that address the way in which our bones are loaded during running. The muscle-bone unit theory refers to the pulling forces created by a muscular contraction. The other references the ground reaction forces through bone when the foot contacts the ground, producing torsional and compressive load. Both mechanisms create macro-trauma which stimulates tissue production and shapes bones geometric structure. However, like other tissues in the body, the activity needs to be progressive otherwise the bone may become accustom and stop adapting. These principles may be used to help runners who may otherwise be stunting adaptation through habitual running load.
In general runners’ bones are healthier than sedentary people. Unfortunately, runners consistently demonstrate lower bone mineral density (BMD) when compared to matched individuals who partake in high impact and irregular movement based sports. A summary of the research of athletes (aged 14-30) found soccer, basketball and volleyball players as well as gymnasts, all displayed greater BMD than those who only ran. A study of young soccer players demonstrated that female players had healthier tibiae than runners and both genders had better density at the spine, femur and calcaneus. In separate studies of track athletes and infantry recruits those who also regularly participated in basketball had up to an 82% reduction in stress fracture risk. Interestingly, in masters athletes those who participated in sprinting had greater BMD than their peers who competed in long distance running. The benefits of diverse loading in youth were also found to protect runners later in life with some up to 50% less likely to sustain a stress fracture.
What seems to be more unclear is the ideal dosage for bony loading. Bone regeneration cycles are suggested to take 3-8months. Studies of humans, mice and turkeys found significant changes after as little as 3 weeks of a jump program. Repetition amount also widely varied between studies from 30 - 350 cycles per week. A study of adolescent females found that a 9-month plyometric program improved only greater trochanter bone strength. Another found plyometric training only benefited those who participated in low osteogenic sports such as swimming. Studies on structure found that rate, magnitude and activity resulted in site specific changes, however, no optimal values for load were presented. No well-known study was found to investigate an irregular, directional and high impact, loading program for the reduction of fracture risk in endurance runners.
It is important to note there are many other factors which influence bone health that have not been explored here. The body needs a plentiful supply of vitamin D and Calcium to build strong bone. To create an optimal environment for this rest and good sleep are also essential. For distance runners who are constantly in a state of low energy availability, bone loading has been found to have little strengthening effects and can be somewhat detrimental if added in addition to their normal training.
Runners want to run. Convincing them to do otherwise continues to remain a great challenge for clinicians, however, it would seem that some variety may strengthen their bones. Youth runners should be encouraged to participate in a variety of sports. Once specialisation occurs, a runner may benefit from incorporating direction and plyometric loading into their training. Unfortunately, the optimal dosage for this is largely unknown.
References
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Gómez Bruton, A., Matute-Llorente, Á., González-Agüero, A., Casajus, J., & Vicente-Rodríguez, G. (2017). Plyometric exercise and bone health in children and adolescents: a systematic review.
Gómez-Cabello, A., Ara, I., González-Agüero, A., Casajús, J. A., & Vicente-Rodríguez, G. (2012). Effects of training on bone mass in older adults: a systematic review. Sports Med, 42(4), 301-325.
Hart, N. H., Nimphius, S., Rantalainen, T., Ireland, A., Siafarikas, A., & Newton, R. U. (2017). Mechanical basis of bone strength: influence of bone material, bone structure and muscle action. Journal of musculoskeletal & neuronal interactions, 17(3), 114-139.
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The dream for many sportspeople is to forge a long and successful career as a full-time professional athlete. However, only very few are lucky enough to experience this, and many more athletes across the world end up showcasing their talents as a part-time or semi-professional athlete.
Rather than having the luxury of dedicating most of their time to training and recovery, these athletes are required to work full time jobs (often labour intensive), and then attend training sessions at the end of a 10 hour work day, with training loads very similar to that of an elite athlete.
This obviously poses a massive challenge to the athlete. Having to try and fit in work, training, recovery, family time, social time and sleep all in the space of a 24 hour day.
Managing these athletes can also be a massive challenge for the sports physiotherapists helping them to rehabilitate their injuries and keeping them out on the park.
As we know, load management is an integral part of progressing through a rehabilitation plan, and also helping to reduce the risk of any niggles or injuries. Over the past few years, even with limited resources at semi professional sporting organisations, physios and S+C staff have become much better at monitoring and analysing player loads from a physical, mental and emotional perspective. However, this is where the real challenge lies in dealing with players who work physical jobs throughout the day. For example, take a player who has suffered a calf strain 10 days ago. We can’t expect a player to tell us exactly how many times he has gone up and down the ladder during his work day as an electrician, but should this be a consideration in how much running he does at training that night?
For the athlete playing at this level, at the end of the day, their paid work is a higher priority for the majority of them over their ability to play sport. This often means that rehabilitation from an injury is compromised or lengthened in time, due to the pressures of having to return to work and feed their families. Take the athlete who has had an ACL reconstruction, but also works as a carpenter. The athlete will be eager to return to full time work as soon as they get the all clear from their surgeon, but will being on their feet all day and repetitively squatting cause a knee effusion that will then hinder their ability to perform and progress their strength work?
As their sport might not be their number one priority in their lives as mentioned, training consistency can also be a challenge in dealing with players at this level. Work and family commitments can sometimes clash with training sessions, with missed training sessions affecting their training load for that week, and potentially increasing their risk of injury in the coming weeks.
The emotional toll that having to fit so much into one day can take on the athlete, is also a vital consideration as a sports physiotherapist at this level. We are in a great position as sports physiotherapists to chat to players to ask them how they are coping. Whilst strapping their ankle, we can gain a lot of information about whether or not the athlete has a rough day or period or time, and whether or not they should have a lighter night on the track to help not overload their nervous system.
Many challenges and questions have been posed above, but the number one question is what can we as sport physiotherapists do to help semi-professional athletes overcome these challenges?
In my opinion, the best thing we can do here is to educate our athletes as much as possible, and focus on the ‘big-ticket’ items to allow them to stay at their best for as long as possible.
The ‘big-ticket’ items for me are:
- Sleep – As we know, sleep has been shown to be the most important recovery technique out there for athletes. Sleep is available to both professional and semi-professional athletes, so this has to be a priority.
- Importance of communication – Empower and encourage the athletes to communicate with coaches, S+C staff and physios so we can better monitor how they are dealing with the challenges of being a semi-professional athlete.
- Training consistency – Missing a 10km training session during the week and not making up for it, can often lead to an injury down the track from my experience. It is up to the S+C coach, physio and athlete to formulate a plan as to how to best make up for this session.
I am sure for those sport physiotherapists out there who work at this level with athletes, these are common challenges for you, along with many more that I have not mentioned. Because of these challenges, I find working with these athletes highly enjoyable and rewarding, and I hope you do too!
In this 13th Episode of The Sports MAP Podcast we chat with Chris Perkins about Athletic Lower Back Pain. Chris is s specialist sports Physiotherapist and has worked at the West Coast Eagles (AFL) for past 16 years. He has also worked extensively with world renowned back pain expert Peter O'Sullivan. In this episode we discuss:
- Chris's professional Journey
- The challenges of blending work in professional sport and running a private clinic
- Managing an athletic lower back pain presentation
- Subjective cues
- Objective assessment
- Common contributing factors and how to address these
- Managing work load
- Imaging & red flags
- The use of non threatening language & communication
- Gym based exercises and low back pain
- And more
Listen to this Podcast via your favorite platform including Apple, Spotify, Player FM & Stitcher.
We hope you enjoy this episode of the Sports MAP Podcast. If you do, please let us know by leaving a review and sharing via Twitter & Facebook.
This episode is brought to you by KangaTech & West Coast Health & High Performance (Perth)
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Tim McGrath is the head physiotherapist for St George Illawarra Dragons in the NRL. He holds a PHD in Rehabilitation of the ACL and return to sport and is the clinical director of Elite Physiotherapy in Canberra. In this episode of the Sports MAP Podcast Tim talks to:
- Critical Mechanism of injury factors
- Preventive strategies in team sports
- Common errors in rehabilitation
- Early loading of the quadriceps
- Change of direction mechanics
- Non surgical vs surgical management
- Return to sport testing
- Tim's career influences and world leading ACL practitioners
- And more
We hope you enjoy this episode of the Sports MAP Podcast. If you do, please let us know by leaving a review and sharing via twitter & Facebook.
Listen to this Podcast via your favorite platform including Apple, Spotify, Player FM & Stitcher.
This is episode is brought to you by IMeasureU