Carbon Plated Shoes And Stress Fractures

Picture from Prodirectsport

I just saw 3 different people wearing carbon plated shoes at the Cold Storage in Holland Village. They were shopping for groceries and definitely not running. On one hand you have someone like me who's still unwilling to run in carbon plated shoes while on the other hand they are a dime a dozen amongst runners now (and people walking in Cold Storage). Most runners use them in training as well, not just at races. 

No running study has studied whether carbon plated shoes (known as advanced footwear technology or AFT) changes running biomechanics associated with bone stress injuries (BSI), or shin splints. The researchers goals were to measure running biomechanics while running in an AFT shoe.

23 runners (11 women, 12 men) with an average age of 25.4 ± 2.7 years were recruited for the study. They ran randomly in 3 different types of running shoes, neutral, lightweight (responsive foam) and AFT at 3 self selected running speeds. A run at their 'training effort', a tempo run and at 5 km race pace.

Biomechanical variables associated with BSI such as cadence, vertical ground reaction forces, ankle and rearfoot eversion forces were measured during each run and shoe condition.

Results show that with neutral running shoes, ankle plantarflexion moment was higher compared to lightweight foam and AFT. There was less rearfoot eversion movement in the neutral shoe compared to lightweight foam and AFT. 

Cadence was lower while running in AFT shoes  compared to neutral or lightweight foam shoes. This is relevant since a longer running stride has been linked (in earlier studies) to BSI in the lower limbs.

Rearfoot eversion velocity (the speed at which your foot rolls down and inwards), or pronation was higher in the lightweight foam shoe compared with both neutral and AFT shoes. There was no significant difference in this between the neutral and AFT shoe.

The authors concluded that there were increases in several biomechanical variables associated with BSI  while running in AFT shoes. Although these changes were small, they tend to accumulate and can contribute to increased forces on bones in the lower limbs.  

The authors suggest that rotating running shoes and gradually using AFT to adapt to the differences may help reduce potential injury risk while optimizing running performance.

Reference

Bruneau MM, Gaudette LW, Sirls E et al (2026). Biomechanics Associated Withe Bone Stress Injuries While Using Advanced Footwear Technology In Elite Distance Runners. PM & R. 18(2): S143-150. DOI: 10.1002/pmrj.70153

Super Shoes, World Records & Navicular Bone Injuries

Picture by Getty images from BBC

On Friday night, Faith Kipyegon set another world record in the women's one mile by almost 5 seconds with her 4:07.64 min timing. Track fans were stunned since previous world records often were improved by mere tenths of seconds. Earlier in June last month, she broke both the 1500 and 5000 meters world record as well while Lamecha Girma set a new mark in the men's 3000 m steeplechase.

Picture by Marta Gorczynska

The ever evolving breeds of super shoes and spikes (have a look above) - those thick springy midsoles with a carbon fiber foot plate by giving higher rebound / energy return must definitely play a part.

Since both elite and recreational runners wear these super shoes in races, almost all of them use super shoes in training too to get a good feel for them too.

Super shoes may store and return more energy than standard footwear so your legs are fresher thus leading to improved running economy. This energy return is possibly from the compression of the midsole cushioning material and the lever effects of the carbon foot plate and a higher toe spring.

Previous studies have demonstrated different biomechanical demands on the foot and lower extremities between super shoes compared to standard competitive running footwear. Runners using super shoes were observed to have decreased cadence, correspondingly longer steps and a longer flight time. 

Red arrows outline the carbon plate

Peak vertical ground reaction forces and vertical impulse per step were also higher when running in super shoes. There were no changes in hip or knee mechanics but differences were observed in ankle and the metatarsophalangeal (foot) joint mechanics. Ankle range (dorsiflexion) during stance phase was found to be reduced during running in super shoes compared to standard competitive footwear (racing flats in the study).

This change in foot and ankle biomechanics introduced by the super shoes may contribute to the navicular bone injuries as previous studies have shown that reduced ankle dorsiflexion and subtalar range are risk factors.

I have written about how an ankle sprain can trigger navicular bone pain in your ankle if you have an accessory navicular bone. Well, there are also runners who get much more serious navicular bone injuries from using super shoes.

A published article documented 5 cases of navicular bone injuries in both elite teenage runners and older professional triathletes that arose from the atypical stresses on the bones and soft tissue from using super shoes.

In all cases, the athletes developed acute pain during or after running in super shoes. 2 out of the 3 teenage runners were steeplechasers while the other ran middle distance. The 2 older athletes were triathletes. They were quickly diagnosed by the experienced healthcare providers that they saw and this hastened their recovery time. Otherwise navicular bone stress injuries can take up to 9 months to diagnose (Saxena et al, 2000). 

Recognizing possible associations of navicular bone stress injuries in runners who present with vague midfoot or ankle pain especially if they use super shoes may be important to identify this high risk injury.

The performance benefits of super shoes are definitely considerable. If you do use super shoes to train and race and do have foot or ankle pain near the navicular bone region, show this article to your health care provider or come and see us at our clinics.

I'm looking forward to see if any more word records are broken at next month's track and field World Championships in Budapest.

References

Saxena A, Fullem B and Hannaford D (2000). Results Of Treatment Of 22 Navicular Stress Fractures And A New Proposed Radiographic Classification System. DOI: 10.1016/s1067-2516(00)80083-2

Tenforde A, Hoenig T, Saxena A et al (2023). Bone Stress Injuries In Runners Using Carbon Fiber Plate Footwear. Sports Med. 53: 1499-1505. DOI: 10.1007/s40279-023-91818-z.

Post Competition Blues

Picture by Getty images from Express

I was reading an online newspaper article in the Guardian (it's also in today's Sunday Times) about how Rafael Nadal was asked whether he would sign up for a magical new foot if it meant losing this year's French Open final. 

"I would prefer to lose the final without a doubt, a new foot would allow me to be more happy in my day-to-day life" he added. 

Injury ravaged Nadal fractured his rib about two months ago, so making this final at Roland Garros already seemed like a miracle. He also has chronic left foot ailment, Mueller-Weiss syndrome (osteonecrosis of the navicular bone), but has consistently dug deep to raise his game and win when it mattered.

Nadal knows that winning is lovely and it gives you a real high, but right after that high there is a big low. Life goes on and life is much more important than whatever title, personal record or victory. The term for this is "arrival fallacy", coined by Tal Ben-Shahar (Harvard Psychology lecturer) which refers to the false belief that once you accomplished a particular goal you will attain a sense of lasting gratification.

I was treating national cyclist Luo Yiwei (above) earlier this week, after she won a silver medal at the recent SEA Games in Hanoi. We discussed about how, once the race day euphoria wears off and our hard earned medals begin to collect dust in our display cupboards, we may be wondering if that was all?

This creeping sense of anti climax that you feel after a race that you've spent months preparing for, is often referred to as post race blues. (I recall feeling like this as well after my GCE 'A' levels. I told myself I'll be out celebrating once the exams were done but it instead felt like a big let down).

Post competition blues is not even tied to race performance. If anything, one can be more prone to post race blues after running the race of your life. When you perform badly, it's easier to ask yourself what went wrong and why and how you can train and race better next time. You can console yourself that next time you will do better.

It is generally more common in amateur athletes than in professional athletes. The pros have to decide when they should retire or whether they should continue to try and make a living as an athlete. This answers the 'is that all?' question as to why they keep going since they are still making a living. 

Not true for the competitive amateur runner who may have to put in 100 km training weeks and utimately has little to show for it other than bragging rights, a medal and a higher chance of a running injury.

Some of my patients who are competitive amateurs say the best 'cure' for post race blues is to simply sign up for another event and set new goals and targets. 

I have felt all that before, when training loses its appeal. For those feeling the post competition blues, I will say that you can definitely indulge in some brooding. Even when I've raced well after a big race, there's always a question of what am I going to do (that's definitely before having kids) in the days after without any concern about getting any training done.

It's a strange feeling not having to train since I've set up, planned, prepared and trained for months and years leading to the big race. It has been my entire life, outside my family and friends.

However, I always say to the athletes that I treat that post race glory is fleeting. I have definitely experienced getting slower in my Saturday rides as I age. It's like there is this invisible hand pulling me backwards when I ride with the younger riders.

That's when I realize that I have to shift my focus. I tell myself to become the best physiotherapist I can be, since I can't be the best athlete I can be anymore. 

Find a way to incorporate what you have learned from your marathon, cycling or football training into your daily life. Apply the same organization, focus, structure and goal setting to your everyday tasks. Then you will find that life and running (or other sporting goals you once had) will be just as exciting and fulfilling.

A younger Rafael Nadal and I at the 2008 Beijing Olympics

We Don't Just Treat Sports Injuries

Many new patients who call our clinic often tell us that they don't play any sports and wonder if they can still see us. To which we reply, "Most definitely!"

As all our physiotherapists are trained to read your body to ascertain how it's positioned in various postures and during movement. We work like detectives, finding the main cause of your problem. We know exactly what we can change to make a difference to your problem and when we might need to refer a patient out to a specialist e.g. neurosurgeon etc.

We specialize in spinal pain and problems, joint pain, muscle strains, joint sprains, nerve related problems (where you might experience pins and needles, numbness or reduced sensation or strength), headaches, and of course injuries that you sustain during sports.

So exactly how different is a sports physiotherapist and a musculoskeletal (meaning muscle and bones) physiotherapist? Having worked in a professional sports setting, treating elite athletes for 10 years, traveling with Team Singapore athletes to the Olympics, SEA, Commonwealth, Asian Games and others and now being in private practice for 12 years , I will attempt to explain the main differences..

The biggest difference would be the time allocated to the athletes and patients. When treating athletes at a professional level, we may sometimes see the athlete 3 times a day. 

Say we have a badminton player who has a niggle in his foot, we get to experiment with taping the player's foot with rigid or Kinesio tape. How can I change his navicular bone position? That alone may determine how well the player trains that morning. Or, if there's a match later that evening we can trial any tape, shoe, or racket earlier in the week before the actual game. 

Oftentimes, the head coach will request specific sessions with injured players to get them up to speed with recovery.

Taping with rigid tape

In an actual game, the physiotherapist has to be paying attention and watching to get clues about the mechanisms of injury. We often need to assess and treat our player ASAP usually within the minute.  I will have in my kit bag, different types of tapes ready, blister kit. splints, nail cutter, scissors, lotions, painkilling sprays etc. in case I need them. We try to be the 'magic' healer, asking questions, cleaning sweaty areas to treat, to allow them to play again.

Yes, Treating elite athletes can be very time consuming and labor intensive.

In a private practice setting (like Physio Solutions and Sports Solutions), the patients are just as eager to be pain free, to get better and to return to exercise. Unlike a competition setting, we get much more time to ask questions and assess thoroughly. Finding and treating the cause of the problem becomes easier. The hands-on, manual therapy we do has huge benefits in changing a patient's condition. However, we may only get to see patients once or twice a week. 

It is, therefore, important to educate patients on what they have to do in the time between appointments. We may teach them self tests and exercises on e.g. their calf range to see how they're progressing. We are easily contactable via text, email or phone if you need to ask questions between your sessions.

In summary, when you become our patient, WE GOT YOU.

Should Youths Run Long Distances?

Picture by Richseow from Flickr

I had a friend ask me on Thursday if his friend's kids should come in to our clinic for physiotherapy or sports massage as they were complaining of feeing 'tight' in their muscles. This year, some of the National School Games are allowed to proceed (after being called off because of Covid-19 last year), so many school athletes are competing again.

I do not recall having such privileges during my time. Perhaps we were hardier or maybe ignorant about recovery and whatever help you can get from sports medicine/ physiotherapy. Besides, I was never into running high mileage during my school days. There were other teenage runners who mentioned that they clocked 100 km a week, while I seldom got above 30 km. We did a lot of quality intervals rather than quantity. Definitely no junk miles. Preparing for the GCE 'A' levels did not leave us much time to run that much either.

There have been studies of youth athletes (not specific to runners) that show sport specialization makes them more prone to injury. Especially those who played their primary sports for more than eight months in a year. These youth athletes had more overuse injuries in the upper and lower limbs compared to those who spent less time in their primary sport.

Youth athletes who participated in their primary sport more hours each week than their age in years had more injuries of any type. They were also more likely to have a history of overuse injuries if time spent training exceeded recommendations for their age. Hence it is important to do different sports for youths. And not to push them.

A running specific study on track and cross country events (989 girls and 1022 boys between 12-18 years) found that youth athletes who specialized had more overuse and previous injuries of any kind compared to those who did not specialize (Post et al, 2017)

Another study (of 126 female cross country and distance track and field athletes) found an increased risk in those runners who specialized compared to those who did not (Rauh et al, 2018).

In order to reduce the risk of running related injuries in the youth runner, we must take into account the complex interaction of various factors, including growth related changes unique to this population. A summary of the risk factors are in the table below taken from Krabak et al (2021).

In addition, the following recommendations are based on expert opinions in the study by Krabak et al (2021). A musculoskeletal screening on your youth athletes for previous injuries, menstrual dysfunction (girls) biomechanical concerns and training errors.

Youth runners should take part in high impact and multidirectional activities focusing on control of the back, hip and lower extremities through puberty to reduce injury and promote bone health.

Make sure your youth runners have at least one rest day a week, 1-2 weeks off every 3 months and limit participation to less than 9 months each year. Single sport specialization should be discouraged until they pass puberty.

Self motivated youths can be allowed to take part in long distance events if they follow an acceptable supervised training program, maintain normal growth in height and weight and are healthy with good nutritional intake.  

So all physical education teachers, coaches and parents, if your youth athlete has BMI < 17.5kg/m2 or body weight below 85 percent of normal for their age, bone density scores of Z > 1.0, untreated eating disorders, high risk stress fractures (in femoral neck, proximal tibial or navicular bone) and female runners without menarche by 16 years old or less than 6 menstrual cycles in the past 12 months then they will require further medical evaluation.

References

Krabak BJ, Roberts WO, Tenforde AS et al (2021).Youth Running Consensus Statement: Minimising Risk Of Injury And Illness In Youth. BJSM. 55: 305-318. DOI: 10.1136/bjsports-2020-102518.

Post EG, Trigsted SM, Riekena JW et al (2017). The Association Of Sport Specialization And Training Volume With Injury History In Youth Athletes. AJSM. 45: 1405-1412. DOI: 10.1177/0363546517690848.

Rauh MJ, Tenforde AS, Barrack MT et al (2018). Associations Between Sport Specialization, Running-Related Injury, And Menstrual Dysfunction Among High School Distance Runners. Athl Trg Sp Health care. 10: 260-269. DOI: 10.3928/19425864-20180918.

"Collapsed" Arches And Tibialis Posterior Muscle Pain

I had a really interesting case involving a triathlete/ runner recently. She had terrible pain in her arches and couldn't even walk around barefoot at home. It had started after she increased her run training recently. The orthopaedic surgeon she consulted had prescribed two pairs (yes two, you read correctly) of orthotics. And he said if they failed she would require surgery. A soft pair for her training and a hard pair while she was wearing her work shoes for her "collapsed arches".

She was advised not to run but was given the green light to bike and swim. Unfortunately, both times she wore her soft orthotics for cycling (and not evening running) her arches hurt after only fifteen minutes and she had stop riding. Even after icing her foot after the ride, her foot still felt sore the next day.

Pretty high eh?

Upon further questioning, she told me she didn't use the orthotic  and was able to walk pain free for 2-3 hours a few days ago in her Havaianas flip flops (or slippers).

However, after she biked again yesterday morning for only ten minutes, the pain came straight back with a vengeance.

When I examined her, her foot was was fairly flat and she had no arches. Her pain was mostly on her navicular bone and it was very tender to touch. I took a quick look at her soft pair of orthotics and noticed that the medial (inner) side of the orthotic was highly built up.

I told my patient I thought it was probably the orthotic irritating her navicular bone since it flared up within such a short time of using it while riding her bike.

Here's how the Tibialis posterior irritates the navicular bone

Other than her navicular bone tenderness, her tibialis posterior muscle was sore upon palpation all the way up her shin. Yes, the tibialis posterior muscle is the very same muscle that causes the much dreaded shin splints in runners.

L tibialis posterior

To make the long story short, I treated her and she's back running happily with no pain. What did I do? I treated her lateral, spiral and superficial back line.

Spiral Line