Sunday, August 24, 2025

Are You A Fast Or Slow Walker?

Let's go for a walk
Walking seems like such a simple thing. We usually do not think about it until you cannot walk properly. My patient who had a recent ACL reconstruction literally had to learn how to walk again.

Walking actually relies on quite a few body systems working together. Your eyes to help you see where you are going.  Your muscles and bones working together to get you places, your heart and lungs to circulate oxygen. Of course you need your brain and nerves to coordinate everything.

Previous studies have shown that walking speed is a significant predictor of life expectancy in older adults. Pooled results from 9 studies involving 34,000 adults aged 65 and older showed that walking speed was significantly associated with lifespan. Men with the slowest walking speeds at age 75 had a 19 percent chance of living for 10 years compared to those with the fastest walking speeds who had 87 percent chance of survival.

Another study found that even amongst healthy adults aged above 65, participants with slower walking speed were 3 times more likely to die of cardiovascular disease compared to those who walked faster.

Did you know that if you are a slow walker you may have a smaller brain compared to a faster walker? Research has shown that how fast you walk to the shops, MRT, or your local coffee shop can predict your chance of a heart attack, being hospitalised or even dying. Your walking speed can even reveal your rate of cognitive ageing.

As we age, these systems start to slow down. Studies show that walking speed is a significant predictor of life expectancy in older adults. This does not just apply to older adults as Rasmussen and colleagues (2019) found that even amongst 45 year olds, a person's walking speed can predict the rate at which their brain and body were ageing.

In that study (Rasmussen et al, 2019) had 904 subjects, all 45 years old born between 1972 and 1973 living in New Zealand. Their health and cognitive function were assessed regularly over their entire lifespans. 

There was fairly huge variation in walking speed among the subjects. You would think that these 45 year olds would have similar walking speeds but some walked as quickly as healthy 20 year olds while others walked as slowly as much older adults.

The 45 year olds with slower walking speeds showed signs of "accelerated ageing" with their lungs, teeth and immune systems were in poorer shape compared to those who walked faster. They also had 'biomarkers' associated with a faster ageing rate such as higher blood pressure, raised cholesterol and lower cardiorespiratory fitness

The slow walkers also had a weaker hand grip strength and found it more difficult to get up from a chair. Other signs of cognitive ageing include lower IQ test scores, worse memory test scores, processing speed, reasoning and other cognitive functions. MRI scans showed they had smaller brains and a thinner neocortex - the outermost brain layer which controls thinking and higher information processing.

Even the faces of the slow walkers were rated as ageing faster than the faster walkers!

The research suggests that the slow walkers' brains and bodies age at a faster rate compared to the quick walkers. There were already signs that these health differences were present from an early age  as researchers were able to predict the walking speed 45 year olds based on intelligence, language and motor skills test taken when the participants were just 3 years old. 

Wow, I am so surprised that there is a link between how fast people walked at 45 years old and their cognitive abilities all the way back to when they were 3 years old. Perhaps walking speed is not only a sign of ageing but a clue to lifelong brain health.

Reference

Rasmussen LJH, Caspi A, Ambler A et al (2019). Association Of Neurocognitive And Physical Function With Gait Speed In Midlife. JAMA Netw Open. 2:2(10): e1913123. DOI: 10.1001/jamanetworkopen.2019.13123.

Sunday, August 17, 2025

Fit But Overweight Or Normal Weight But Unfit

Picture from Truenorthwellness
What if you were fit but overweight and even obese compared to being unfit but normal weight. Which do you think is better?

A new meta-analysis pooled results from 20 prospective cohorts thus investigating nearly 400,00 people (Weeldreyer et al, 2025). Participants were categorized by body mass index (BMI) as normal weight, overweight or obese. Their carodiorepiratory fitness (CRF) were measured by maximal exercise testing to determine if they were fit or unfit based on age adjusted VO2 max. This was to determine if BMI or CRF predicts mortality risk better.

This meta-analysis is different from earlier ones since it includes more women. It also has participants from a broader age range, geographic backgrounds and health status. Better statistics all round. Findings more generalizable and results more precise.

The reference group - normal weight and fit was compared to all other combinations. Compared to the reference group, those who were both overweight but fit and obese but fit, both groups had virtually the same risk of dying from any cause. About 4 percent lower and 11 percent higher respectively, which was not statistically significant. Being fit protected against being overweight and obese for all-cause mortality.

Not so good news for the unfit. Those who had normal weight but were unfit had a 92 percent higher all-cause mortality risk. The risk was similarly high for unfit and overweight (82 percent higher) and even higher for the unfit and obese (104 percent higher).

For cardiovascular disease mortality, the differences between weight categories were more pronounced. The fit but overweight had a 50 percent higher risk while those fit and obese had a 62 percent higher risk than fit individuals with normal weight. Note that neither was significant, although it meant that being fit protected one against the risk of dying from cardiovascular disease.

Now for those who were unfit for cardiovascular disease mortality, the numbers were not pretty, in fact they shyrocketed. 104 percent higher risk for normal weight, 158 percent for  overweight and 235 percent for the obese.

In short, being unfit more than doubled mortality risk for many cases, regardless of BMI, while being fit can netralize the impact of carrying extra weight.

These findings show that BMI alone is a weak predictor of health and improving cardiorespiratory fitness can cancel out much of the risks associated with a higher BMI.

Perhaps BMI is not a good indicator. One may have a high BMI and yet be muscular and fit - the Amercian football players in the NFL have high BMI values. They are classified as obese, but they are actually very fit and muscular.

Should we be more concerned with increasing fitness levels over weight loss during public health awareness? There seems to be more emphasis now on weight loss and eating less processed food rather than increasing physical activity. 

This study suggests boosting fitness levels should be at the top of the list, not just as a replacement for tackling obesity. Studies like this show that physical activity is definitely more important than diet for those who want to live to a ripe, old healthy age. Not to say that diet does not matter. But fitness is king. Perhaps our Ministry Of Health should angle some incentives?

Reference

Weeldreyer NR, De Guzman JC, Paterson C et al (2025). Cardiorespiratory Fitness, Body Mass Index And Mortality: A Systematic Review And Meta-Analysis. BJSM.59:339-346. DOI: 10.1136/bjsports-2024-108748

Monday, August 11, 2025

Aircon Mall Marathon

Picture from Arabnews
I remember meeting some Singaporeans who lived in Doha when Team Singapore went to compete in the 2006 Asian Games. They told us during the hottest months temperatures went up to over 50 degrees Celsius. How can one exercise safely I remember asking myself back then.

Well, while Singapore celebrates turning 60 on August 9th, 2025, a sprawling shopping centre in Dubai organized a "Mallathon" on the same day.

Back by the Dubai government, it aims to encourage exercise during the hottest month in United Arab Emirates (UAE). They make use of Dubai's giant malls which are otherwise empty at that time. 

Runners can take part in organized 2.5km, 5 km and 10 km races at designated malls complete with podium presenattions and prizes.

One can also wait in line to use electric bikes that powered blenders to make healthy smoothies after exercising.

Perhaps our Singapore malls can do the same. To help revive our ailing retail and food and beverage scene.

Happy National Day Singapore!

Sunday, August 3, 2025

Are The Chinese Brands Surging Ahead?

My first observations about someone are always about their footwear. I have done this ever since I was a teenager, I would be curious about people's shoes. I always look at what shoes a person is wearing especially if they are a runner. Of course as a physiotherapist now, I do the same.

If you are a runner you may or may not have heard of Anta, Li-Ning, Qiaodan, Xstep. They were usually unheard of a few years ago and dismissed as inferior to Nike, Adidas, Asics and New Balance (sorry if your brand is not listed). 

However, Chinese Super running shoes with their carbon fiber plates and super foam are increasingly becoming mainstream compared to before. Selemon Barega (Tokyo Olympics 10 000 m winner) switched from Nike to Li-Ning 3 days before the race and won the 2025 Seville marathon in an impressive 2:05:15 hours.

Some Chinese running brands have already set up shops in Singapore. Li-Ning has 2 stores here while Anta now has 11 stores after opening their first in 2023.

There may still be perceptions of Chinese Super shoes as being lower quality and/ or durability. They are definitely cheaper costing between S$150-200 a pair compared to more than S$300 for Super shoes from established brands.

I have definitely noticed some of my patients using Chinese super running shoes. My patients say that they are not only cheaper than the established brands, they seem to have even more energy return and propulsion. Personally, I have not tried any of the Chinese running brands yet.

Not just with running shoes, it seems. If you happen to be a cyclist you may have heard of Winspace or X-Lab? Some cyclists still regard cycling tech from China as cheap and/or  counterfeit. Too good to be true or too dangerous to use because of high failure rate.

Cycling World Tour team XDS Astana is using a carbon fiber bike made by X-Lab. This is the last team Mark Cavendish, who has won the most stages in the Tour De France rode for albeit on a different bike before he retired last year.

Winspace wheels are much cheaper compared to Campagnolo, Enve or Lightweight wheels. Lightweight's Meilenstein Art wheels cost $8000 while Winspace's Lun Hyper go for $1500. At almost the same weight, with a deeper rim profile, it ticks all the boxes. Winspace wheels have even been rated as excellent by engineering expert Hambini. They are also UCI approved. Matter of time before they get used at a World Tour level race or even at the Tour De France.

Will I consider Winspace's wheels? I currently use Campagnolo's WTO 45mm Bora wheels on rim brakes. I am not a fan of disc brakes on road bikes. Personally, I think bicycles have gotten more expensive and more complicated with disc brakes. I am sure bike manufacturers like the higher margins that come along with them too. When it becomes impossible to find a rim brake wheelset from a mainstream brand I may have to switch to them since Winspaceare committed to supporting both disc and rim brakes.

See how cheap they are
I still look at cheap carbon wheels, shoes, ceramic pulleys on AliExpress and Shopee (above). For reference, my Ceramic Speed pulley wheels alone cost $500 a pair. I'm not telling you the price to brag, but to make a point. I'm tempted to use them, but horror stories that show up online have steered me away so far.

2 Pirelli tubes on the left
Except for my inner tubes. Previously I used the very expensive Pirelli TPU inner tubes for my bike. I am now using TPU inner tubes made from China. They are so many different brands now. China has created many cheaper alternatives to the popular TPU-based inner tubes from Pirelli or Tubolito that cost $30 compared to $8 ones from China. Well, far so good, they have not let me down yet.

What do you readers think? Are Chinese brands taking the world by storm? BYD cars are now most popular in Singapore while mainland Chinese food and beverage brands are also growing their brands here.

Sunday, July 27, 2025

What Helps Prevent Muscle Atrophy During Immobilization

Which leg was immobilized?
We see many patients with muscle atrophy on their affected limb. This definitely happens after surgery where whole body or single limb immobilization may be necessary. This leads to decreased muscle size and strength.

What strategies are there to mitigate this? You may be very surpised.

20 male participants (average age 33) took part in this study (Labidi et al, 2024). All were former competitive athletes, primarily in athletics, now working as fitness coaches. 

The participants were split into 2 groups. They had 2 weeks of single lower leg immobilization with a orthopaedic walking boot . They were taught to use crutches and instructed not to weight bear on that leg. This was followed by 2 weeks of supervised rehabilitation before return to sport (RTS). 

The participants underwent 4 weeks of a standardized training program to ensure a common training base before the immobilization procedure. There were 5 sessions (3 resistance, 2 endurance) of training each week. They also received 4 nutritional sessions inclusive of face-to-face consults with a nutritionist and educational videos to standardized daily energy and protein intake throughout training, immobilization and rehabilitation phases.

Picture from SIU Med
The participants then underwent 4 weeks of supervised training. The 1st group had whole body heat therapy (HEAT) while the 2nd group had sham treatment (SHAM) throughout the immobilization and rehabilitation periods.

During the immobilization period, the participants received 11 passive interventions of 60 minutes. The HEAT group sat in a heat chamber at 48 to 50 degree celcius at 50% relative humidity (at 0 m altitude). 

During the rehabilitation period, the participants received 5 active interventions (conditioning) of 60 minutes. The HEAT group performed the sessions in the heat chamber at 35 degrees Celcius and 60 degress relative humidity at 0 m altitude. 

The SHAM group sat in an altitude chamber, set at only 200 m (to create a placebo effect while avoiding any effect of altitude). The temperature was at 24 degree celcius and 40% relative humidity.

Ready for the results? All of the following were measured pre-immobilization, post-immobilization and at RTS. Muscle strength (isometric and isokinetic) were measured. Muscle volume was measured by MRI and ultrasound while muscle biopsies were also obtained. Maximal isometric strength for the calf muscles (plantarflexion) was lower at RTS compared to pre-immobilization in SHAM. 

Isokinetic strength during a fatigue test was higher at RTS compared with pre-immobilization in HEAT but not SHAM. 

Shape of muscle and muscle thickness were lower at post-immobilization compared with pre-immobilization only in SHAM. Cross sectional area of the soleus and the medial, lateral gastrocnemius were decreased in SHAM. Only the medial gastrocnemius was smaller in cross sectional area in HEAT.

The results indicate that using heat therapy during immobilization and rehabilitation reduces muscle atrophy and maintains calf strength in healthy humans. Repeated heat exposures should be considered to counteract muscle atrophy during immobilization.

I'm not sure that it's practical to get in a sauna with a cast on but maybe with a boot or back slab that can be removed temporarily? I would do it if I wanted to return to sport badly enough or maybe if I'm old and wanted to prevent muscle bulk and strength while awaiting healing to happen. For those with with an aversion to heat, definitely no go.

Reference

Labidi M, AlhammoudM, Mtibaa K et al (2024). The Effects Of Heat Therapy During Immobilization And Rehabilitation On Muscle Atrophy And Strength Loss At Return To Sports In Healthy Humans. Orth J Sp Med. 12(10). DOI: 10.1177/23259671241281727

Sunday, July 20, 2025

Our Words Affect Pain

Picture from Coregymball
It may be just words you think. Perhaps not. Recently published fascinating research suggest that how healthcare providers describe an injury can have a direct impact on a patient's pain

Not only were the patients blinded (a technique used to minimise bias), the patients also did not know they were part of a study.

Picture from article
50 recreational runners with Achilles tedinopathy took part in the radomized trial (pictured above). They ran 3 times a week. Runners in the experimental group received diagnostic information of tendon pain that highlighted reversible changes in muscle function as their primary problem. They did not hear any reference to tendon pathology.

The control group received an explanation of tendon pain that prioritised irreversible structural tendon pathology as the cause of pain.

The primary outcome measure was how much pain the runners had during a standardised hopping task measured on a scale of 0-100. Secondary outcomes were how stiff the lower limbs were hopping and time in seconds for pain to ease after completing the hopping task.

The diagnostic information immediately affected pain intensity during the hopping task. The average pain score was 25.4 in the experimental group versus 36.7 in the control group.

Time to ease (no pain) after hopping was near identical in both groups. Lower limb stiffness was higher in the experimental group. Note that higher leg stiffness is better for leg hopping because increased leg stiffness allows for greater force production and more efficient energy transfer. This leads to higher jump heights and faster movement.

This is a really intriguing area of research. We now have data showing that information from healthcare providers during the first visit has an immediate effect on pain. The language we use during clinical interactions can be powerful, shaping our perceptions and pain responses. This knowledge should change how we interact with our patients. 

However, we need to also be able to do this in our clinics without compromising the accuracy and necessary medical information.

Reference

Travers NJ, Travers MJ, Gibson W et al (2025). The Content Of Diagnostic Information Has An Immediate Effect On Pain With Loading In People With Morportion Achilles Tendinopathy: A Randomized Clinical Experiment. Bra J PT. 29(5). DOI: 10.1016/j.bjbt.2025.101244

Sunday, July 13, 2025

Quadrilateral Space Syndrome

R posterior arm picture by Mickeymed.com
I treated an 11year old girl recently with pain in her quadrilateral space. What space you may ask? The quadrilateral (or quadrangular) space is a tiny window or space that the axillary nerve and other blood vessels (posterior circumflex humeral artery) exit from the shoulder to the back of the arm. It's boundaries are teres minor on top, the humerus (arm bone) on the right, teres major below and the long head of triceps on the left. The axillary nerve supplies the deltoids and the teres minor muscles. 

Picture from Clinical Anatomy & Op Surgery
This young patient plays softball for her school and is her team's first choice pitcher. Softball pitching is different as the ball is thrown to the batter using an underhand motion. The goal while pitching is similar to baseball, to get the batters out by strikes or preventing them from reaching base. 

Injury or compression in the quadrilateral space often leads to pain, numbness in the posterior shoulder/ arm and/ or weakness in those areas.

This condition is much more common in young athletes participating in arm over head sports like swimming, throwing and volleyball in their dominant hand. But she did do many overhead throws prior to having this pain in her posterior shoulder and arm. In addition, her coach also started her on a weight training program in the upper body and arms.

Injury or compression in the quadrilateral space often leads to pain, numbness in the posterior shoulder/ arm and/ or weakness in those areas. There is often tenderness in the quadrilateral space on palpation. 

My patient also had some paresthesia (numbness, tingling sensations) on the outer shoulder and elbow when I checked her upper limb tension test. Her shoulder external rotation strength was also noticeably weaker on her thowing arm, which should not be the case.

Once we determined the cause, treatment was easy as we simply had to 'widen' the quadrilateral space while also addressing the overhead throwing overuse and the sudden increase in weight training. A simple phone call to her coach,who happened to be a previous national pitcher and patient of mine solved that.

Reference

Pocellini G, Brigo A, Novi M et al (2025). Different Patterns Of Neurogenic Quadrilateral Space Syndrome: A Case Series Of Undefinied Posterior Shoulder Pain. J Orthop Trauma. 26(1). DOI: 10.1186/s10195-024-00813-y.