What Does The Fibularis Longus Muscle Have to Do With Knee Pain?

R Peroneal Longus (Peroneal Longus)

After 3 previous knee surgeries, and also seeing many patients (with knee pain) over the last 25 years I've learnt a lot about treating knee pain. So I was pleasantly surprised to learn more and hopefully get even better at treating knee pain.

Many of our patients come to our clinic with patellofemoral joint pain (PFP) or pain in the front/ side of the knee especially during loading activities like running, walking, squatting, jumping and going up and down stairs. Studies have shown that 23 percent of all adults will get PFP, and 50 percent of them will experience PFP that lasts up to 20 years!

I've written previously that the hip often affects the knee too. Well, a group of researchers found differences in fibularis longus (or peroneal longus) muscle size and even activation between individuals with PFP and healthy controls. This was done using ultrasound imaging in weight bearing (Jaffri et al, 2024).

Of the 60 subjects (30 healthy, 30 with PFP) investigated, there was a statistically significant result for the healthy group in the size (larger) and activation for the fibularis longus (or peroneal longus) muscle.  The group with knee pain had smaller fibularis muscle and it did not work (or switch on) as quickly as those without knee pain.

Note that besides its role as a evertor of the foot, the fibularis longus works together with abductor hallucis longus to stabilize the medial longitudinal arch after heel strike. Hence slower activation and smaller (weaker) of the peroneal longus muscle in a weight bearing position may contribute to arch flattening in PFP subjects. This add to faulty mechanics at the foot and ankle joints. 

This further explains the fact that the smaller (and weaker) the fibularis longus is, the higher likelihood of the foot pronating. This leads to knee valgus (knee facing inwards), which is a major biomechanical abnormality in individuals with PFP.

I am certain not every health professional reading this will agree since clinical treatment guidelines to treat PFP are still being developed as there is a lack of agreement about what actually causes PFP. Not everyone agrees that hip adduction, increased knee internal rotation, foot pronation etc causes PFP.

If you have persistent knee pain that does not seem to go away, please show the health professional treating you this article. Other than the hip, your fibularis longus muscle may help with your knee pain. And I am not talking about just strengthening it.

Better still, come see us at our clinics.

Reference

Jaffri A, Schwarting A and Beallow A (2024). Impairments In Peroneal Muscle Size And Activation In Individuals With Patellofemoral Pain In Weight-bearing Position. J Foot Ankle Res. 17: e12014. DOI: 10.1002/jfa2.12014

Fiblaris logus is part of the lateral line

10 Bodyweight Squats Or Walk 30 minutes?

Last week I wrote about how a fast or slow metabolism does not influence your weight gain or weight loss. For those of us who run or exercise to manage our weight, it definitely does burn calories while you are exercising, but it does not boost your metabolism, at least not in the long term. 

Well, I can suggest a fairly simple way to improve your blood sugar regulation better than a single 30 minute walk if you're pressed for time. Also helps to lower cancer and cardiovascular related mortality.

A recently published study (Gao et al, 2024) on overweight and obese subjects who either sat uninterrupted for 8.5 hours or had interruptions while sitting with matched energy expenditure and duration. A 30 minute walk at 4 km/hr, sitting with 3 minutes walking at 4km/hr or squatting 10 times every 45 minutes.

The authors found that doing 10 body weight squats every 45 minutes or short frequent walking breaks during a 8.5-hour period of sitting improved blod sugar regulation better than a single 30 minute walk (at 4 km per hour).

These superior benefits seemed to be associated with increased muscle activity intensity in their targeted muscle groups during frequent transitions from sitting to activity.

These brief, intense bursts of activity (bodyweight squats in the study) termed 'exercise snacks' offer a simple yet strong strategy to mitigate the health risks associated with our sedentary lifestyles. It is not too difficult to get up from sitting and do 10 bodyweight squats every 45 minutes (or when you can). You can also do burpees or run up stairs to break up sedentary periods. Those at home may want to do some dumb bells/ kettle bells swings.

Of course some other people may prefer to walk outside for fresh air, sunlight meeting other people and psychological/ mental health benefits. Or a combination of exercises and walks. Works well too. Go on and add some some exercise snacks into your day.

References

Gao Y, Li QY, Finni T ey al (2024). Enhanced Muscle Activity During Interrupted Sitting Improves Glycemic Control In Overweight And Obese Men. Scan J Med Sci Sp. 34(4): e14628. DOI: 10.1111/sms.14628

Stamatakis E, Ahmadi MN, Gill JMR et al (2022). Association Of Wearable Device-measured Vigorous Intermittent Lifestyle Physical Activity With Mortality. Nat Med.28: 2521-2529. DOI: 10.1038/s41591-022-02100-x

Will My Metabolic Rate Slow Down As I Age?

Picture from Genesispersonalfitness

Looks like we have been very wrong about our metabolic rates. Whether our metabolic rate is fast or slow, it cannot predict weight gain. 

Metabolisms varies by 20 percent or more from person to person regardless of activity level or body composition (Rimbach et al, 2022). So for those of us who run or exercise to manage our weight, yes it does burn calories, but it does not boost our metabolism, at least not in the long term. 

The researchers also found that if you happen to be on the skinnier side, it is not that you have a faster metabolism (Rimbach et al, 2022).

The researchers measured metabolism using doubly labeled water. Participants in their studies drank water containing hydrogen and oxygen isotopes, which researchers can track in the body. How quickly they lost the isotopes through peeing, sweating and even breathing were monitored. These enabled them to ascertain how many calories are burned in that time, or what is known as total energy expenditure i.e. metabolism.

The total energy expenditures studied were measured at 2 time points, ranging from 2 weeks to more than 8 years. Body size and composition were adjusted for since more cells burned more calories and fat and muscle burned calories at different rates. 

The researchers found that the subjects' daily energy expenditures did not change over time. A person with high metabolism today will have it high in a few months or even a few years. Likewise, a person with slow metabolism today will still have it slow in a few months or a few years.

Here's the good news. The researchers found that having a slow metabolism did not make people more likely to gain weight. Nor did having a fast metabolism less likely to gain weight.This is attributed to the human brain's outstanding ability to match calories consumed to calories burned in the long run.

So, running or any exercise is not a magic metabolism booster. Exercise is complex and it affects how our body regulates all its cells, which in turn affects hunger, fullness, immune function and even behaviour. 

Those who exercise will obviously see day to day fluctations in the calories burned. More on long runs/ hard days compared to recovery days. Our bodies adjust how much energy we use during our non exercise hours to keep the total caloric burn within a fairly narrow range.

So, you do not gain weight as you age because your metabolism slows down (Pontzer et al, 2021). We have all been mislead by this myth. We should not use it as as excuse. You gained weight because we do not move and/ or exercise as much and because we may have lost some muscle mass.

Reference

Pontzer H, Yamada Y, Sagayama H et al (2021). IAEA DLW Database Consortium. Daily Expenditure Through The Human Life Course. Science. 373(6556): 808-812. DOI: 10.1126/ science.abe5017

Rimbach R, Yamada Y, Sagayama H et al (2022). Total Energy Expenditure Is Repeatable But Not Associated With Short-term Changes In Body Composition. Nat Commun 13,9. DOI: 10.1038/s41467-021-27246-z

Cold Play?

ST 100524

I just wrote about how cold (ice) immersions were not effective last week! And Straits Times does a full page article on the front of their Life Section today (100524).

"I noticed a significant improvement in my alertness and reduced muscle soreness after including cold therapy ....." said a business owner selling ice baths.

No, evidence says cold immersions does not help with recovery. Actually cold immersions inhibits recovery. Researchers (Roberts et al, 2015) have found that cold water immersion after hard exercise suppressed signaling pathways associated with recovery. This suppression lasted for several days.

The newspaper article also credited Wim Hof (the Dutch iceman) for popularising cryo or ice therapy - just like my post. Purveyors of commercial health and wellness have definitely jumped on the same bandwagon. I cannot comment on the various beauty and skincare benefits (such as reduction in cellulite and what not) as touted by the wellness professionals quoted. Please do your due diligence.

Reference

Roberts LA, Raastad T, Markworth et al (2015). Post-exercise Cold Water Immersion Attenuates Acute Anabolic Signaling And Long-term Adaptations In Muscle To Strength Training. J Physiol 593(18) : 4285-4301. DOI: 10.1113/JP270570.

Can Cycling Lower Your Risk Of Knee Arthritis?

Picture by Dennis Thong

I have written previously on what causes osteoarthritis (OA). Definitely not because of overuse nor a mechanical wear and tear process. Especially for those without any previous history of knee truma/ injury, there is very good evidence that OA is actually due to metabolic factors. Well, now a new study (Lo et al, 2024) suggests that cyclists are less likely to develop OA in their knees.

Lo et al (2024) studied 2600 older adults with and without knee OA using knee X-rays, subjective knee pain, and a questionnaire regarding their lifetime history of various physical activities during 4 periods of their lifes: 12 to 18 years old, 19 to 34, 35 to 49 and over 50. 

The study used 3 different outcomes. Persistent knee pain, OA based on X-rays (radiographic OA) and symptomatic OA (having both knee pain and radiographic OA. Note that what is seen on X-ray (OA knees) does not always correspond to pain. This means that some subjects had knee radiographic OA but NO pain.

Almost half the subjects reported some history of cycling and these subjects were less likely to have OA in their knees. How much less? Those with any history of cycling were 17 percent less likely to have knee pain, 9 percent less likely to have radiographic OA and 21 percent less likely to have both. 

Half of those who cycled reported only cycling regularly during one of the 4 age periods, usually the youngest age period from 12 to 18 years old.

Those who cycled during 1,2,3 or 4 of the periods studied reduced their risk of symptomatic OA (i.e. painful knees) by 17, 19, 28 and 43 percent. Meaning lifelong cyclists reduced their risk of symptomatic OA by nearly 50 percent.

The researchers also found that subjects with a history of swimming, strength training and running had lower rates of OA. This is consistent with previous evidence that running DOES NOT ruin your knees despite what every non runner and ex runner you know will insist running does.

You may love watching the beautiful game, but a history of playing the beautiful game (football) even just as a teenager bumped up knee OA risk by a factor of 2. This elevated risk remained even after adjusting for BMI, suggesting that the problem is likely related to acute knee injuries suffered while playing football. 

Picture by Dennis Thong

The researchers concluded that more cycling is associated with less knee pain and favorable to knee health and should be encouraged. 

If you have never cycled previously and would like to start, do note that almost half or the current or former cyclists in the study had radiographic evidence of OA. A quarter of them had symptomatic OA (painful knees). Is cycling better for OA once you do develop OA compared to say running? Is cycling capable of slowing its progression? Currently, we still do not know.

Those of you who have been always been cycling, you definitely have another reason to do so. 

Reference

Lo GH, Richard MJ, Kriska AM et al (2024). Bicyling Over A Lifetime Is Associated With Less Symptomatic Knee Osteoarthritis : Data From The Osteoarthritis Initiative. Med Sci Sp Ex. DOI: 10.1249/ MSS 0.0000000000003449

All pictures by Dennis Thong. Many thanks to Dennis and Eugene Phua for the pictures.