Male And Female Hearts Respond Differently To Exercise

Picture from Intermountain Health

Our hearts respond differently when we lift weights or perform endurance workouts. Our heart muscles get stronger, more efficient and they also get physically larger in some cases.

However, both men and women respond differently to weight training and endurance training. How different? A randomized crossover study examined how the heart's structure and function change after 12 weeks of endurance versus weight training in males and females (Naylor et al, 2025).

64 untrained but healthy individuals (38 females, 26 males) were randomized to either 12 weeks of endurance training (running or cyling 3 times a week) or 12 weeks of weight training (progressive weights, 3 times a week).

The 2 groups swap training routines after a 12 week cooling off rest period. This allowed researchers to compare how the same participants responded to both types of training.

The results showed that overall, endurance training led to healthier heart adaptations than weight training. weight training in men led to thicker heart walls but this led to worse diastolic function (relaxation), potientially increasing stiffness in walls of the heart.

Endurance training improved the size of the left ventricle and its ability to pump blood (systolic function) and to fill with blood (diastolic function) efficiently.

Men's hearts responded more to weight training, the left ventricle size increase significantly. However, men showed signs of worsened diastolic function after weight training. Their hearts became stiffer.

The women in the study showed no major heart changes after weight training. Their hearts also adapted more to endurance training. Left ventricle size increased in both men and women in the study , but the women showed better diastolic function improvement. 

The womens' hearts also adapted more to endurance training. Left ventricle size increased in both men and women, but the women showed better diastolic function improvement. 

Both men and women had no major changes in systolic function after endurance training.

So what does this mean for runners or endurance athletes and those who favour gym exercises/ weight training? 

Those who favour weight training need to include aerobic training so that their heart walls do not get too stiff to impede diastolic function.

If you are looking at heart health, endurance training improves heart structure without adding stiffness to the walls, this is true especially for women. Since endurance athletes will do more aerobic training they should still include weight training for better heart health and performance.

Even though endurance training improves heart function, weight training definitely benefits health (especially strong bones) and performance too. This is why we do both.

Reference

Naylor LH, Marsh CE, Thomas HJ et al (2025). Impact Of Sex On Cardiac Functional Adaptation To Different Modes Of Exercise Training: A Randomized Cross-Over Study. Med Sci in Sp Ex. DOI:10.1249/ MSS.0000000000003654

Exercise For Your Life

I saw a patient earlier this week for her shoulder and neck pain. She goes to Aspire 55 for weight training twice a week. We were chatting about how strength training has made her stronger and able to handle aging better. 

She mentioned that she visited someone she knew who stopped exercising at Aspire 55 for 6 months. She wanted to check in on her and was shocked at how frail her friend had become.

Frailty can occur in older adults and is characterized by a decline in physical abilities and an increased vulnerability to adverse health outcomes. 

If not treated, frailty can lead to a number of adverse health outcomes such as falls, disability, hospitalizations and even death. Its presentation and diagnosis can vary as well as being overlooked or misdiagnosed as part of the normal aging process.

Evidence suggest that the prescription of a comprehensive exercise program which includes strength, endurance training, mobility and balance improves function, targets frailty and improves quality of life (Vazquez-Guajardo et al, 2024).

The picture above shows the cardiorespiratory fitness that we need for our activities of daily living. If our fitness level drops below these thresholds we will not be able to 'afford' the metabolic cost of tasks needed to remain independent. One of many reasons to stay active for as long as possible. 

Exercise is therefore more than just fitness and looking good. It also gives you the ability to stay independent and resilient for longer. Resilience represents the ability to withstand adversity and remain in homeostasis despite the physical, psychological and social challenges of aging.

No matter what age you are , keep exercising to prevent, mitigate and perhaps even reverse frailty's trajectory.

Reference 

Vazquez-Guajardo M, Rivas D and Duque G (2024). Exercise As A Therapeutic Tool In Age-Related Frailty And Cardiovascular Disease: Challenges And Strategies. 4098): 1458-1467. DOI: 10.1016/cjca.2024.01.005

Cardio Before Or After You Lift Weights?

Picture from Diamondback Fitness

Last week's post was about weekend warriors, who did not have enough time to exercise during weekdays. My patient who read that post was asking me if she should lift weights or do cardio first if she wanted to do both back to back. I told her it depends on her athletic goals and how much time she can spare working out. 

So should you lift weights first or cardio (or aerobic training) first?

I suggested weight training first followed by cardio (or aerobic exercises). Weight training involves external loading with barbells, weights, kettlebells and resistance bands and has a more acute injury risk if already tired. Especially after a longer aerobic session, your muscles are fatigued and lifting weights after that will elevate your injury risk.

One would usually not be able to lift as much or perform that many reps compared to starting with strength training. Especially if you decide to lift heavier weights.You will definitely do a better job if your muscles are fresh.

Note that if you lift weights before your aerobic exercise it will also inhibit your aerobic performance. Research shows that there will be a reduction in speed, power and stamina. 

Actually when I used to race triathlons, I would often do weight training and then cycle and/ or run after (brick training). I'll be fatigued after the weight training which is the state I would be in after swimming and cycling before attempting the run section anyway. So that made sense for me to always run when I'm already tired to simulate race conditions. 

Lifting weights prior to aerobic exercise will not significantly increase your risk of injury compared to tackling heavy weights when you are already tired. Do aerobic training and weight training on different days to optimize both if you have time. If you are thinking of doing both, go with weight training first.

An exception to the rule for this would be the warm up. Warming up with a bit of light cardio (stationary bike or elliptical etc) prior to weight training (or any other workout) will help prime your muscles, increase blood flow, get your mental focus and nervous system ready for action. 

You can work both strength and cardio simultanesously in the same workout when you perform circuit training or HIIT as it is now commonly called. By minimizing your rest time and prioritizing your work efforts, your heart rate remains elevated while working your muscles to simulate hypertrophy. 

You do get the best of both worlds, burning calories and endurance boosting of aerobic conditioning and the muscle building and power from strength training. Just do not do them every day as your body will not have time to recover sufficiently between sessions.

Reference

Conceicao M, Cadore EL, Gonzalez-Izal M et al (2014). Strength Training Prior To Endurance Exercise: Impact On Neuromuscular System, Endurance Performance And Cardiorespiratory Responses. J Hum Kinet. 30(44) : 171-181. DOI: 10.2478/hukin-2014-0123

Strength Matters More Than Size

Pawel Poljanski's legs at the Tour De France

My colleague was wondering why I was not 'big' (or muscular) despite exercising regularly. I explained to her I was more Type I muscle dominant (or slow twitch muscle) as most endurance athletes are. Those who have predominantly Type I muscle fibers are lean, not big and muscular.

Her obesrvation is accurate. I actually lift weights twice a week and even though I can squat 90 kg, my thighs are still skinny.

I also explained to her that it is better to be strong than have big muscles. Weight training can make you stronger and your muscles bigger. They are both related since bigger muscles are usually stronger. However, they are not identical. You can get stronger without adding muscle bulk. 

This happens when the signaling from your brain to your muscles become more efficient and how effectively your muscle fibers are recruited. You can add muscle without getting stronger, this typically happens when you gain weight.

Strength is also a much better predictor of cognitive performance than muscle mass. Storoschuk and colleagues (2023) studied 1424 adults above 60 years of age between 1999 and 2002 in a health and nutrition examination study (NHANES). These subjects had DEXA scans to assess body composition, leg strength tests, a digit symbol substitution test (cognitive test) and questionnaires that assessed physical activity habits. The DEXA scan is used to determine how much muscle one has in their arms and legs and fat-free mass index (FFMI), which shows total muscle to height.

The figure above presents the benefits of different variables on cognitive performance. The farther on the right each square is, the greater the cognitive benefits. You can see that low FFMI (low muscle mass) has no significant effect on cognitive scores, while peak leg force (a measure of strength) definitely have a significant benefit. Those who did resistance training (or weight training) for at least once a week has an even stronger effect.

Strength explained about 5 percent of the variance in cognitive scores, while muscle mass explained only 0.5 percent. Low strength levels raised the risk of premature death, but low muscle mass did not. In contrast, another study by Tessier et al (2022) found that low muscle mass predicted more rapid cognitive decline over a 3 year follow up period, after accounting for differences in strength. Perhaps it would be premature to conclude that muscle mass (being big) does not matter.

Confused? Storoschuk et al (2023) explained that there is a difference between the muscle you get from physical activity and muscle you get in the process of gaining weight. Greater muscle mass may just be a larger body size rather than greater strength, which does not seem to translate into protection from cognitive decline and other health benefits.

Moreover the conflicting results from the 2 studies are possible due to different popolulations, different cognitive tests and different sample sizes. 

My take on this? It is good if you have big muscles and I will still lift weights twice a week to at least maintain and avoid losing what I have. Getting stronger is much better, and that is the main reason why I do weight training. Even though I do not seem to gain muscle I am able to increase the reps and quality of the exercises I perform. 

So, to ward off cognitive decline, strength training is just as important as aerobic exercises.

References 

Tessier A, Wing SS, Rahme E et al (2022). Association Of Low Muscle Mass With Cognitive Function During A 3-Year Follow-up Among Adults Aged 65 To 86 Years In The Canadian Longitudinal Study On Aging. JAMA Netw Open. 5(7): e2218826. DOI: 10.1001/jamanetworkopen.2022.19926

Storoschok KL, Gharios R, Potter GDM et al (2023). Strength And Multiple Types Of Physical Activity Predict Cognitive Function Independent Of Low Muscle Mass In NHANES 1999-2002. Lifestyle Med. 4: e90. DOI: 10.1002/lim2.90

Scoff Not At Elastic Resistance Bands

Tan Howe Liang (pictured below) is still the strongest man I know. Yes, the same Tan Howe Liang that won Singapore's first ever medal at the 1960 Rome Olympics. He was a senior gym instructor at the gym at the old National Stadium and we often bumped into each other when I was still working there. I was always amazed when he told stories about his training days. Mind you, he could still squat with very heavy weights whenever I saw him train then. 

Silver at the Rome Olympics, SNOC picture

But don't fret if you don't have easy access to a gym or other fancy, expensive gym equipment. Other than your bodyweight, elastic resistance bands can be great for strengthening muscles too.

Not many of you may believe me if I said that training with elastic bands can be just as effective as training with weights for strengthening muscles.

The following systematic review and meta-analysis is possibly the first to compare the effects of strength training for strength gains with elastic tubes and bands versus conventional devices (dumbbells and weight machines).

The search identified 365 articles, of which eight studies were within the inclusion criteria comprising of 224 individuals between 15 to 88 years old. All subjects were performing regular strength training. In these groups were physically active individuals, athletes, individuals with coronary heart disease and moderate chronic obstructive pulmonary diseases.

Results of the meta-analysis showed that there is no superiority for both upper and lower limbs between training performed with elastic bands and training with free weights on strength gains. This was consistent across groups mentioned above and also when compared with a control group in the elderly, individuals with osteoarthritis and even fibromyalgia. 

The authors conclude that training with elastic bands is just as good as conventional resistance for promoting strength gains in different populations using diverse protocols. 

Having elastic bands at home to train with eliminates the need to travel to the gym and this may be more practical and a lot cheaper for certain people who may find it difficult to go to a gym. patients will have greater adherence to strengthening programs too. 

Personally I feel elastic bands are great for strengthening and correcting muscular imbalances. I still use them on a very regular basis. Especially after my accident.

Exercising with bands in my back brace in 2013

Do not let anyone tell you that you are wasting time if you are not using heavy weights and expensive equipment. Effective strength training can be achieved with body weight, free weights and especially elastic bands too.

We have managed to rehabilitate many national athletes back from injury and even avoid surgery in many cases using elastic bands to strengthen the injured areas. Especially in cases when a weight plate/ bar is initially too heavy and risk further injury and load to the person's joints.

Reference

Lopes JSS, Machado AF, Micheletti JK et al (2019). Effects Of Training With Elastic Resistance Versus Conventional Resistance On Muscular Strength: A Systematic Review and Meta-analysis. Sage Open Med. DOI: 10.1177/2050312119831116.

Don't neglect the legs

How To Increase Range Of Motion

All the kids posed for this picture

A typical comment from many of our patients is that they have been stretching all the time but their muscles still feel tight. 

Range of motion (ROM) is necessary as part of our health and important during sports performance. And static stretching is often prescribed to get better ROM gains. We know from previous research that static stretching is effective in improving our range of motion. 

However, the latest systematic review/ meta-analysis shows that strength training (ST) is just as effective as static stretching in getting improvements in ROM.

The researchers pooled data together and found eleven good quality studies comprising 452 participants to derive the following results.

Interventions lasted between 5 and 16 weeks while training frequency ranged from two to five times a week. Subjects included healthy sedentary subjects, subjects who already participate in ST subjects with fibromyalgia and subjects with chronic neck pain. There were also elderly adults who had difficulties in one of four tasks, transferring, bathing, walking and going to the toilet.

Both ST and static stretching groups showed significant improvement in ROM in seven of the studies. Differences between the groups were non significant. They did not find any significant differences in active and passive ROM for both ST and stretching. Dynamic stretching did not improve ROM in any of the groups.

You must be wondering how ST helps to improve ROM that is not statistically distinguishable from static stretching. The authors wrote that ST with an eccentric focus requires the muscles to produce forces in a lengthened position. This is what helps improve ROM. They also found that concentric strength training improves ROM when full range is required.

One study demonstrated significant reductions in pain associated with increases with strength, suggesting that decreased pain sensitivity may be another mechanism in which ST help increase ROM. Another mechanism may be an improved agonist-antagonist co-activation helping ROM gains.

The authors concluded that both ST and static stretching can improve ROM both in the short and long term suggesting that there are both neural and mechanical factors at work. Both ST and stretching can be prescribed to help improve ROM. If one does not respond or adhere well to a stretching program, they can switch to strength training instead.

What does that all mean you (if you did not understand the discussion above)? If you're looking to get an increase in your range of motion say in your knee joint, you can do eccentric strengthening exercises with some stairs at home. This previous article explains everything in a simple manner.

Just remember that static stretches are best done after exercise as just one bout of static stretching can slow you down as well as reduce your maximum strength.

Reference

Afonso J, Ramirez-Campillo R, Moscao J et al (2021). Strength Training Is As Effective As Stretching For Improving Range Of Motion: A Systematic Review And Meta-analysis. DOI: 10.31222.osf.io/2tdfm

Spinal Manipulation Helps With Hip/ Knee Weakness In Otherwise Healthy People

Wow, this article definitely caught my eye as a single manipulation on the spine in healthy subjects increased the lower limb strength, at least in the short term.

The subjects were found to have lower limb musculoskeletal dysfunction along with muscle weakness. Those with knee and hip weakness who are otherwise healthy had large strength gains.

Strength training will hypertrophy muscle and increase strength over a period of six weeks though the authors suggested that weakness can persist despite muscle hypertrophy. They suggested this occurs in the early stages of joint pathology or when there is limb or spinal joint immobility which may then inhibit muscle activation.

The authors also presented evidence of three randomized controlled trials (these are Level 1b evidence of moderate quality) that showed immediate small to large effect size muscle strength gains immediately after spinal manipulation.

The authors suggested that spinal manipulation to particular spinal segments after screening for specific muscle weakness can increase short term strength. This will present a chance for efficient intervention as patients benefit by starting an exercise program to train the new muscle function gained. This provides extra incentives and more motivation for the patients to keep training.

What remains unclear though are the neuro muscular mechanisms through which the spinal manipulations increases strength.

Hmmmm, as you can read, I'm intrigued by the possibilities of increasing strength with a simple manipulation of the spine, but not convinced yet.

I would still suggest that those with true hip and knee weakness (and no other condition) engage in a strength training program.


Reference

Wong CF, Conway L et al (2020). Immediate Effects Of A Single Spinal Manipulation On Lower-Limb Strength In Healthy Individuals: A Critically Appraised Topic. J Sp Rehabil. June 2020: 1-5. DOI: 10.1123/jsr.2019-0372.

Will You Lose All Your Strength During The Circuit Breaker If You Cannot Lift Weights?

Lunging with a 10 kg bag of rice 

We are currently at the end of week 3 of the circuit breaker (or modified lock down) in Singapore. Most of my patients who strength train are not able to take part in their usual exercises and training regimes. This is true especially for my bodybuilding and avid gym going patients, since gyms and other exercise centers are closed.

Not many of them have an ideal home gym for strength training during this period. So for them, there's a real threat of detraining (loss of strength) for them and other sporting populations. Any loss in muscle strength, power, muscle atrophy may affect future performance, injury risk and self esteem.

A recently published study (Blocquiaux et al 2020) studied older male patients (58-70 years old) during a 12 week whole body resistance training program. The subjects stopped training for 12 weeks and then resumed training for another 12 weeks.

Decent strength gains were made at 8 weeks (22%), and 12 weeks (36%) in leg strength (similar for upper limb).

What was most interesting was that all the strength gains (36%) during the initial 12 weeks were not completely lost during the 12 weeks of no training. 14% was lost during this period.

When the participants resumed training for another 12 weeks, they were stronger at the end of the second 12 week period than the first. It took them 8 weeks or thereabouts to regain what they lost in 12 weeks.

So if we were to compare with our current circuit breaker period (3 weeks and counting), don't be too discouraged. You can probably gain back what you lost. Hopefully it will take less time too looking at that study (Blocquiaux et al 2020) . For those of you who bike, run, row or do other endurance sports, there is a similar pattern observed for cardiovascular fitness too.

Now, lets look at female subjects. Correa et al (2016) studied a group of older women, and this time the period of no training was a whole year. The female participants gain an increase of 75% in strength after an initial 12 week training period. Much of these gains were lost after a year, back to baseline levels. However, after another 12 weeks or training, they gained a lot of this strength back, they were just 15% off their first 12 week training period.

So, another glimmer of hope for those of you who strength train. Though I'm hoping our circuit breaker will not be a year long!

If you make do with whatever you can find at home to strength train to failure albeit with a lighter weight, you will stave off some of the losses. That's what I try to do.

Many people are dealing with all sorts of mental and motivational issues other than physical and financial ones so exercise may be way down on their list of priorities. But if you can still exercise, it will definitely lift your mood Ludyga et al (2020).


References

Blocquiaux S, Gorski T et al (2020). The Effect Of Resistance Training, Detraining And Retraining On Muscle Strength And Power, Myofibre Size, Satellite Cells And Myonuclei In Older Men. Expt Gerontology. 133: 110860. DOI: 10.1016/j.exger.2020.110860

Correa CS, Cunha G et al (2016). Effects Of Strength Training, Detraining and Retraining In Muscle Strength, Hypertrophy And Functional Tasks In Older Female Adults. Clin Physiol Funct Imaging. 6(4): 306-310. DOI: 10.1111/cpf.12230.

Luduga S, Gerber M et al (2020). Systematic Review And Meta-analysis Investigating Moderators Of Long-term Effects Of Exercise On Cognition In Healthy Individuals. Nat Human Behav. DOI: 10.1038/s41562-020-0851-8

Is CrossFit Safer Than Running?

Picture by Kylie Siu 

There, I thought that headline will catch your attention. More on that statistic later in the article.

CrossFit comprises of calisthenics, Olympic weightlifting, powerlifting, plyometrics, high intensity interval training (HIIT), gymnastics, running, rowing and other exercises. Participants complete daily WODs (workouts of the day) to build cardiovascular endurance, stamina, strength, flexibility, power, speed, agility etc.

CrossFit Inc was founded by Greg Glassman and Lauren Jenai in 2000 in Santa Cruz, California. It was started earlier as Cross-Fit In 1996. After the couple fell out, Glassman bought over her share with a huge loan.

CrossFit was also made popular by military personnel, law enforcement agencies, fire departments etc who can do WODs anywhere by accessing it online.

I've seen many CrossFit athletes come to our clinic, mostly by word of mouth referral. I'm told by some of them that they like to see me because I don't ask them to stop training as they're often when they see someone else when they have an injury.

Other doctors and other health care practitioners often tell them that CrossFit has a high risk of musculoskeletal injury. I usually allow them to train (modified of course) while getting them better. One such patient asked if I can write about CrossFit injuries.

So here's what I found from published articles. Those of you reading this because of the title, thank you for reading this far.

Most of the research suggest that CrossFit is not more dangerous than other strength based training. like weight or power lifting. Researchers found CrossFit results in roughly 2.1 injuries per 1000 training hours. It was actually higher for endurance sports like running. Recreational running resulted in 8 injuries per 1000 hours of training. For novice runners the figure shot up to 18.

Athletes new to CrossFit (less than 6 months) were definitely injured more often. This finding is important and coaches and athletes need to focus on correct movement patterns. Workouts need to be modified for beginners.

Common injury locations were in the knee, lower back and shoulder. Majority of the injuries were reported as chronic/ overuse in nature. Possible causes included bad/incorrect form to lift a heavier weight, fatigue, old injury and too little/ bad coaching.

Because the WODs were constantly changing and varied, CrossFit athletes are often sore or will have some discomfort from training. This can result in an inability to do the next day's workout fresh, resulting in a higher chance of injury.

Majority of injuries we see in our clinics tend to be chronic/ overuse in nature. They can definitely be remedied by coaches through modification of complexity, volume and intensity of workouts. The healthcare practitioner treating such athletes will need to modify their training around their current injuries. A simple example is an athlete with a Right lower limb injury is still able to continue CrossFit by training the upper body and L lower limb.

Bear in mind that CrossFit for general strength and fitness is different from competing in CrossFit competitions. While competing, you need to go all out with fixed weight and exercises. When performing workouts for general fitness, you can reduce the weight, drop the reps or change to a similar but less technical exercise.



References

Claudino JG, Bourgeois F et al (2018). CorssFit Overview: Systematic Review And Meta-analysis. Sports Med Open. 4:11. DOI: 10.1186/s40798-018-0124-5.

Mehrab M, De Vos R et al (2017). Injury Incidence And Patterns Among Dutch CrossFit Athletes. Orth J Sp Med. DOI: doi.org/10.1177/2325967117745263.

Poston WSC, Haddock CK et al (2016). Is High Intensity Training(HIFT)/ CrossFit Safe For Military Fitness Training. Mil Med. 181(7): 627-637. DOI: 10.7205/MILMED-D-15-00273.

Running, Weight Training And Your Tongue Muscles

Michael Jordan and his tongue. I like Rodman too!

Last week, I wrote about why strength training and aerobic exercises are both critical to us aging well. I'm sure most of us kinda knew that already.

Turns out now that exercise, particularly endurance exercises may be useful in preventing and perhaps even treating sleep apnea and dysphagia (difficulty swallowing). Your tongue, just like the rest of your body, was made to move.

Let me present the latest benefits of exercising. VanRavenhorst-Bell and colleagues (2018) has shown that exercise is associated with greater tongue strength and endurance. Just as written before, not all exercises are equal.

Before you start laughing or stop reading this post, consider the following information.  You'll need good strong tongue muscles to keep your airways open while you sleep (to prevent sleep apnea). If the slow twitch muscle fibers at the back of your tongue lack endurance, it increases your chances of mouth breathing and sleep apnea.

The fast twitch muscles near the front of your tongue is important for swallowing. Our tongue muscles do get weaker as we age, which can lead to dysphagia (difficulty swallowing), making it easier for you to choke.

Ideally, you you need great endurance at the back of your tongue to avoid airway breathing problems and great strength at the front of your tongue to prevent swallowing problems.

In their study comparing weight lifters and runners who trained at least four times a week, weightlifters were found to have greater maximal tongue strength and runners have greater endurance. Reason being weightlifters would use the front of the tongue to produce forceful inhales and exhales while the rhythmic panting of endurance runners would help in greater tongue endurance.

Here's Mo Farah with his tongue out

If you're keen to know how they test tongue strength have a look here.

So here's another reason reinforcing that there's way more physical benefits to exercising then what we know. We are definitely made to move.

Reference

VanRavenhorst-Bell HA, Coufal KL et al (2018). A Comparative Study: Tongue Muscle Performance in Weightlifters And Runners. Physiol Rep/ 6(22): e13923. DOI: 10.14814/phy2.13923.

Read the article here.

Here's 2 pictures of Michael Jordan when he was way younger.

Winning shot for North Carolina in 1982 in college

With a young John Stockton 

All the pictures I took with my iPhone X from this book "For the love of the game".

Since Michael Jordan and Dennis Rodman retired, I hardly watch the NBA now.

Aerobic Exercises Key To Aging Well?

Me on the left. Picture by Jeffrey Keng from Cycleworx

Slightly more than a year ago, I wrote that strength training may be just as important (if not more) than aerobic exercises. Why? Strength training has been found to decrease rates of early and cancer related death.

And earlier this year I disagreed with a funded study by Les Mills International when the article suggested that lifting weights was more beneficial for losing weight compared to running or cycling (aerobic exercises).

Now, some new research seems to show that aerobic exercises (like running, cycling, rowing or swimming) can make our cells younger. That same study found that weight training may not cause the same physiological changes in our cells.

Way back in 2009, a study found that competitive middle-aged runners had extended telomeres compared to inactive people of the same age. What are telomeres? All of us have telomeres at the tips of our chromosomes. Telomeres help protect our cells from damage and have been found to shorten and fray as a cell ages.

Many of the researchers in that 2009 study came together for this recent study to investigate whether exercise would change our telomeres.  They also wanted to know what type of exercise were needed and whether intensity played a part. It is hypothesized by the scientists that exercise helps lengthen the telomeres.

The researchers recruited a group of healthy middle aged men and women who did not exercise. They were tested for  their aerobic fitness and telomere length. In addition, blood markers of telomerase (an enzyme that influences telomere length) were tested as well.

Some in this group were randomly assigned to continue with their lives as normal as a control group. They did no exercises.

Others started a supervised program of brisk walking or running for 45 minutes three times a week or a high intensity interval program of four minutes of strenuous exercise followed by four minute rests with this repeated four times.

A third group took up weight training, doing a circuit of resistance exercises three times a week.

Heart rates were monitored and the exercise program was carried out for six months. Results were tested after this and all the subjects who exercised were found to be more aerobically fit.

At molecular level however, there were differences. Those who did the aerobic exercises and interval training had much longer telomeres than before starting the exercise program and more telomerase activity.

Those who weight trained and those in the control group (who did not exercise) had no change in telomere length. Some even had shortened telomere lengths.

Those who did weight training produced less nitric oxide, which is thought to affect telomerse activity and contribute to lengthening telomeres.

Even though weight training was strenuous, overall heart rate was lower compared to running in the study. This results in less blood flow and probably less physiological response from the blood vessels.

The researchers suggested that exercise needs to be aerobically taxing to extend telomere length and slow cellular level aging. In this aspect, endurance exercise was clearly ahead of resistance training.

The findings do not indicate that weight training does not combat aging as it also helped improved fitness, which itself is a very important indicator of longevity.

Like I wrote before, current research shows that both strength training and aerobic exercises are necessary to be healthy and functional. So run, bike or lift weights, (or whatever exercise you prefer) as they are all beneficial, it's much more important to keep moving.

I wanna for live a long time, so I lift weights too

References

Werner CM, Furster T et al (2009). Physical Exercise Prevents Cellular Senescence In Circulating Leococytes And In The Vessel Wall. Circulation. 120 (24): 2438-2437. DOI: 10.1161/CirculationHA.109.861005.

Werner CM, Hecksteden A (2018). Differential Effects Of Endurance, Interval And Resistance Training On Telomerase Activity And Telomere Length In A Randomized Controlled Trial. Euro Heart J. ehy585. https://doi.org/10.1093/eurheatj/ehy585.

Strength Training Just As Important (If Not More) Than Aerobic Exercises

Lifting before running

After our two beautiful boys came along, my wife used to just run as there was not much time for any other exercise. She found big benefits from minimal running. It improved her mood and energy levels while also lowering her risk of heart disease and stroke.

After a few years of just running, she felt that her fitness level was stagnating and that she was losing strength. So earlier this year, (along with two friends), my wife has been doing twice weekly strength training sessions at the Holland Village F45  gym.

A recent study found strength training just as important (if not more than aerobic training) and can add years to your life. This is the largest study so far (over 80,000 adults) to compare mortality outcomes of different types of exercise people did.

Researchers found that strength training (both gym machines and body weight) decreased the risk of early death (23 percent) and cancer-related death (31 percent).

Earlier I wrote about how weight training can also help solve Singapore's diabetes problem as highlighted by our prime minister during the 2017 National Day Rally. This study lends more weight to my suggestions to help Singaporeans get healthier.

Moreover, the World Health Organization's (WHO) physical activity guidelines suggest 150 minutes of physical activities and two days of strength training every week.

Seems like my wife's twice weekly strength training sessions at the Holland Village F45 is spot on with WHO's guidelines.

For those intimidated by gyms, (be it costs or images of heavy weights), the researchers suggested that body weight exercises like sit-ups, push-ups, lunges and triceps dips done in your own home or local park can be just as beneficial.


Reference

Stamatakis E, Lee I, Bennie J et al (2017). Does Strength Promoting Exercise Confer Unique Health Benefits? A Pooled Analysis Of Eleven Population Cohorts With All-cause, Cancer, and Cardiovascular Mortality Endpoints. Am J Epidemiology. kwx345. https://doi.org/10.1093/aje/kwx345.

How Singapore Can Solve Our Diabetes Problem

In our National Day Rally, Prime Minister Lee Hsien Loong highlighted that 1 in 9 Singaporeans has diabetes. And of these, an average of 1200 undergo amputations every year!

I was quite shocked at the sobering figures that he cited. Three in 10 Singaporeans above the age of 60 have diabetes. If you break in down by race, 2.5 in 10 Chinese over 60 have diabetes, half of Malays over 60 years old and six in 10 Indians over 60 are affected.

PM Lee then urged Singaporeans to get regular medical check ups to know if they are diabetic or are at risk and suggested solutions to counter it. He then recommended that Singaporeans exercise more, suggesting that the easiest way to do so is "just walk  a little bit more every day".

If possible, I would definitely suggest including weight training (also known as strength training or resistance training).

In case you think weight training is only for bodybuilders pumping iron for beefy biceps and bulging pecs, current evidence shows that weight training - whether with a light dumbbell or your own body weight may be the best exercise for lifelong overall function and fitness.

Here's what most important. Research has shown that weight training helps with improved insulin sensitivity among people with diabetes and pre diabetes. Twice weekly weight training sessions helped control insulin swings (and body weight) among older men with type-2 diabetes.

During weight training, our muscles are rapidly using glucose (or blood sugar). This energy consumption continues even after you finish your strength training session. This is especially beneficial for anyone at risk for metabolic conditions like Type-2 diabetes, high blood pressure, and unhealthy cholesterol levels making weight training the most effective remedy.

In addition, weight training can strengthen our bones and improve our posture through bone remodeling. Weight training stimulates the osteoblasts (bone building cells) to build more bone. Weight training is also superior to aerobic exercise for enhancing and maintaining total body bone strength. And that's probably another post.

That's why I bought a Olympic bar, squat rack and got some free weights earlier this year as I realize I was losing muscle mass.

Showing my boy how it's done

Reference

Ibanez J, Izquierdo M et al (2005). Twice-Weekly Progressive Resistance Training Decreases Abdominal Fat And Improves Insulin Sensitivity In Older Men With Type 2 Diabetes. Diabetes Care. 28(3): 662-667. DOI: 10.2337/diacare.28.3.662.

How Quickly Do You Lose Fitness When You Stop Training?

Picture of Singapore Stan Chart marathon by RunSociety from Flickr

Well, many of you've just done your last race of the season. Yes, after the Standard Chartered Singapore Marathon 2016 this morning it's off season time at last.

Now it's time to take some much needed rest, both physically and mentally and not worry about training for a while.

The most common question and worst fear among my patients who run (or race triathlons) is how quickly do they go out of shape if they stop running (or training).

Ever wondered how long before detraining kicks in? Well, just as you don't become a fast runner overnight, you don't lose your fitness that quickly too. Nothing goes up in a straight line, there'll be some peaks and valleys. Likewise you don't lose your fitness overnight too.

Okay, first the good news. Research on detraining or how quickly you go out of shape shows that those who are less well-trained have less to lose. This make sense considering the elite athletes have further to fall.

Elite athletes can lose up to half of their aerobic fitness within the first 12-21 days of not training. They can then lose half of their remaining fitness in the next 12-21 days and so on. The bad news, those who've trained for a few months have a slower decline, but lost all fitness within 4 weeks.

Most studies suggest that an elite athlete's VO2 max levels drop 7 percent if they stop training for 12-21 days. They can lose another 9 percent from days 21-84.

One major reason for the quick fitness decline is the loss of blood volume. In the first 12-21 days that you stop training, you can lose up to 500 milliliters of blood. It's a simple supply and demand situation. When you stop training, you take away the demand.

The body loses the ability to bring oxygen to the muscles and you also have less fluid available for sweating (which cools the body).

The good news is with retraining, you can regain blood volume in a week although it takes a while for your red blood cells to grow again.

Other than blood volume, your mitochondria cell density, lactate threshold and your ability to oxidize fat stores all deteriorate.

Researchers have found it difficult however to measure time to regain your fitness. A common suggestion is that for every week lost, it takes two weeks to regain that previous level. The reason for this all those functional capabilities mentioned above.

When I was still racing, I used to take two weeks off at the end of the season. Yes, two weeks of no swimming, running, cycling and weight training. This allowed me to recuperate both physically, recharge mentally and also to spend time with my family, loved ones and friends. And when its time to train again, I'd be raring to go.

Do bear in mind that not all systems in your body detrain or retrain equally. Do consider your age. Runners in their 20's can resume training as though they never took time off. Older runners will take longer. 

Strength gains (from weight training) are not lost as quickly as aerobic (or cardiovascular fitness) and it usually takes 4 weeks before you start to lose peak muscle strength and maybe that will be another article later on.

So congrats and well done to those of you who ran this morning and make sure you take that well deserved time off.

References

Coyle EF, Hemmert MK et al (1986). Effects Of Detraining On Cardiovascular Responses To Exercise: Role Of Blood Volume. JAP. 60(1): 95-99.

Joyner MJ and Coyle EF (2008). Endurance Exercise Performances: The Physiology Of Champions. J Physiol. 586(1): 35-44. DOI: 10.1113/j.physiol.2007.143834.

Fitness Research For 2015

Picture by Elliot Brown from Flickr

As the year draws to a close, I looked back at all the articles I've read and I realise that there were many articles written by research scientists on exercise and brain health this year. 

One of the more persistent themes seems to be that in order to live long, age well and maintain both a nimble and sharp mind we need to be physically active. Many of the new studies demonstrated previously unexplored ways in which exercise helps our brains and minds.

Exercise, usually running seems to increase the number of neurons in our brains and helps sharpen thinking skills and mood as we age.

Fortunately the exercise periods needed seems to be much shorter than we expect. 

One article I read on brain imaging was really interesting. A group of Japanese researchers found that the brains of fit older men were almost as efficient as the brains of young people. 

The researchers found that the aerobically fit older men's brains used fewer resources during thinking compared to the out of shape men of the same age. This is similar to someone fitter using less energy to perform a physical task compared to someone less fit. 

So at least for me personally, a good reason to keep running regularly to make sure my brain stays sharp.

Another study looked at whether and how weight training and muscles affect the brain. Healthy, older women who completed the year long, twice weekly weight training sessions of light weight training showed fewer and smaller brain lesions in their brain's white matter compared to women of the same age who only completed a stretching/ balance training session or going to the gym once a week.

White matter connects and passes messages to different parts of the brain, which is crucial for memory and thinking.

While I was still training and competing, I used to go to the gym thrice weekly. Since 2009, I haven't at all. Looks like I may have to introduce some weight training/ resistance exercise in the coming new year. 

I do have some heavy tiles/ drain covers in my back garden which I've hauled around before so I don't have to weed the garden so often. Believe me, they're heavy too. I may have my own "nature gym"in my back garden after all ......

So here's wishing all our readers, patients and friends a great year ahead in 2016.

References

Bolandzadeh N, Tam R et al (2015). Resistance Training And White Matter Lesion Progression In Older Women: Exploratory Analysis Of A 12-Month Randomized Controlled Trial. J Am Geriatr Soc, 63(10): pp 2052-2060. DOI: 10.1111/jgs.13644.

Hyodo K, Dan I et al (2015). The Association Between Aerobic Fitness And Cognitive Function In Older Men Mediated By Frontal Lateralization.NeurolImage. 125: pp 289-230. DOI:10.1016/j.neurolimage.2015.09.062.

Men Do Get It

Picture by German Tenorlo from Flickr

Mention osteoporosis and usually what comes to mind is that someone has fragile or brittle bones and that someone is usually female. If I'm a guy I don't have to worry about it.

It will probably shock you then that estimates in America show that almost two million men have osteoporosis and 16 million men have osteopenia (bone density that is lower than normal but not low enough to be considered osteoporotic). The contributing factors are not doing correct exercises and ageing.

Medication can help improve bone health but recent studies show that strength training and jumping exercises are a healthy alternative.

Researchers studied a group of osteopenic men for a year comparing the effects of weight training and jumping exercises. Both groups of participants completed 60-120 minutes of targeted exercises each week.

The jumping exercises included jump squats, forward hops, split squats, box jumps and depth jumps. The weight training group did squats, modified dead lifts, lunges and calf raises with weights.

Both groups also took calcium and a vitamin D supplement during the study period.

Six months into the research, both groups of men had a significant increase in whole body bone mass, including the lumbar spine (low back) and they maintained the increases for 12 months.

The weight lifting group also had a significant increase in hip bone density. At the end of the study, all the participants had sufficient vitamin D.

The participants also reported low pain and fatigue suggesting that the exercises have good compliance rates and can be easily adapted in a real life setting.

The researchers concluded that targeted exercise with the correct supplements are an effective way to improve bone density rates to reduce risk of developing osteoporosis in men.

Reference

Hinton PS, Nigh P et al (2015). Effectiveness Of Resistance Training Or Jumping-exercise To Increase Bone Mineral Density in Men With Low Bone Mass: A 12-month Randomized, Clinical Trial. Bone. 79: 203-212. DOI: 10.1016/j.bone.2015.06.008.

Protein Before Bed Builds Muscle

Night time snack before zzzzz

You can't simply build muscle eating lots of protein. To build muscle you need a combination of resistance training and protein. Recent studies show that the most effective way to trigger muscle growth is to spread your protein intake in several doses of 20-25 grams throughout the day.

A group of researchers have previously demonstrated that if you consume protein right before sleeping it can increase the rate protein synthesis (the process of making protein) by 22 percent during overnight recovery from exercise.

This same group of researchers now wanted to know if consuming protein before bed would increase the muscle adaptive response to weight training.

They did a 12 week double blinded study on a bunch of volunteers who weight trained three times a week. The subjects drank either a protein drink or placebo before bed. The protein drink contained 27.5 grams of protein and 15 grams of carbs.

The results showed that the group that had the protein drink had significantly greater improvements in muscle strength, muscle size and even muscle fiber size (done by muscle biopsy).

The subjects were already consuming diets that were fairly high in protein (1.3 grams/kg) and they also had a protein snack (10 grams of protein) after each workout.

How should you snack up on your pre bedtime meal? A cup of milk has about eight grams of protein, and if you had some toast and peanut butter that will probably do the trick.

Don't forget to do strength train too.

Reference

Snijders T, Res PT et al (2015). Proten Ingestion Before Sleep Increases Muscle Mass And Strength Gains During Prolonged Exercise Training In Healthy Young Men. J Nutri. 145(6): 1178-1184. DOI: 10.3945/jn.114.208371.