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

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

Your Workout Today May Trigger A bright Idea Next Week

Picture from Triana et al (2024)

What if I told you your exercise session today can trigger a bright idea next week? That's exactly what a recent study by Finnish researchers found. They tracked a person's brain and behavioural activity for 5 months using brain scans and data from smart phones and wearable devices. 

This research (Trinan et al, 2024) was unusual since few brain scan studies involve such detailed monitoring over months. Using wearable technology in this study was crucial, especially since brain scans (while being useful) only shows the subject lying still for 30 minutes. 

2 distinct patterns were identified by the researchers. A short term wave that lasted under 7 days and a long term wave by up to 15 days. The short term wave reflects rapid adaptations like how focus is affected by poor sleep although it recovers quickly. The long term wave suggests more gradual, lasting effects, especially in areas tied to our attention and memory.

The study found that our brains do not respond to our activities of daily living in immediate, isolated bursts. Our brain activity evolves in response to our sleep patterns, physical activity, mood, and respiration rate over many days. This means that your exercise session or a restless night from the previous week can still affect your brain. Hence your memory, cognition and attention can be affected well into the next week.

It is a great study linking brain activity with environmental and physiological data as tracking our brain changes in real time can help detect mental health and neurological disorders early. This allows for earlier interventions and better outcomes.

Even though this study was not focused exclusively on exercise, the results showed that we definitely need a consistent exercise routine and maintain good sleep habits for our overall well being. I find myself particularly sensitive to these as I age. 

Reference

Triana AM, Salmi J, Hayward NME et al (2024). Longitudinal Single-subject Neuroimaging Study Reveals Effects Of Daily Environmental, Physiological, And Lifestyle Factors On Functional Brain Connectivity. Plos Bio. DOI: 10.1371/journal.pbio.3002797

Many Physiotherapists Cannot Prescribe Exercise?

Teaching Ronald Susilo how to ride

I definitely don't agree with the following research (Barton et al, 2021) which concluded that physiotherapists cannot prescribe physical activity and exercise well for people with muscle and joint pain/ problems. Let me explain further.

I was asked to go to court last year to be questioned by the lawyer of the insurer (for the truck driver) for my accident in 2013. Yes, after waiting for almost 7 years, and numerous adjournments by the other party, the hearing was finally scheduled. 

Their lawyer questioned why I needed physiotherapy after my accident and he added that "isn't physiotherapy just doing some exercises". If so then I would not need to attend any more sessions and just do the exercises at home and the insurer would not have to pay anymore.

I explained that he (and perhaps the general public) may think when you see a physiotherapist, all the physiotherapist does is to teach you strengthening exercises for your pain or condition. But teaching strengthening exercises isn't the only thing physiotherapists do. At least not at our clinics anyway. 

But physiotherapists in Singapore can definitely teach exercises, especially in the hospital setting. That's what my patients tell me anyway.

Back to the study. 1,352 physiotherapists from 56 countries were surveyed. Most agreed that their job requires exercise prescription of aerobic exercise (75%) and resistance/ strength training (89%) to patients with muscle and joint pain/ problems. 

38 to 50 percent of the physiotherapists reported that they were not confident and had no training/ skills to prescribe aerobic exercise and resistance/ strength training (50 to 67%). Only 11% were able to give the correct guidelines for aerobic exercise and resistance/ strength training (21%).

62 to 79 percent  felt that their packed schedule (seeing too many patients), access to equipment/ space and lack of opportunity to attend professional development affected their ability to prescribe guidelines for effective exercise. 

The authors concluded that many physiotherapists lack training and knowledge to give advice for physical activity, and to prescribe resistance/ strength training and aerobic exercise to people with muscle and joint pain.

The general public (and the lawyer that quizzed me) thinks that all a physiotherapist does is teach exercise for treatment. Is that what you think?

Reference

Barton CJ, King MG, Dascombe G et al (2021). Many Physiotherapists Lack Preparedness To Prescribe Physical Activity and Exercise To People With Musculoskeletal Pain: A Multi-national Survey. Phy Therapy in Sport. DOI: 10.16/j.ptsp.2021.02.002.

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.

Can Running Help Stop You From Eating Junk Food?

My personal favorite

Any of you having a craving for junk food? I do, all the time. In fact as I'm writing this, I am having a huge craving for potato chips.

How do I not succumb to this urge? Well, it seems that people whose brains have a strong dorsal-lateral prefontal cortex (DLPFC) section may have greater self control when it comes to eating behaviour.

What the heck is that?

Well, the DLPFC is near the front portion of your head in case you were wondering. Researchers zapped that area (with a coil placed near the subjects scalps near the hairline) to temporarily decrease brain activity in the DLPFC of the subjects in their study.

Guess what? When the participants were zapped in that area, they had more food cravings and also ate more junk food compared to subsequent tests when they received a sham zap.

With that zap, the participants were almost totally interested in high calorie snacks (Pringles potato chips and milk chocolate in the study).

In fact they mostly ignored the more healthy food options that were also available.

The researchers suggest that improving your DLPFC function can improve dietary self control, prevent obesity and may even help manage Type II diabetes.

How to you make your DLPFC function better? Studies have shown that running and other aerobic exercises are known to enhance DLPFC function. Getting adequate sleep and avoiding alcohol have also been shown to help.

Hmmm, this is strange. When I used to train a lot previously, I would often eat all chips, chocolate, drink lots of Coke etc. I thought all that training was supposed to help strengthen my DLPFC??

Now that I'm not racing and training much I would not dare to eat as much for fear of putting on too much weight. I guess after my accident, I've changed my eating habits as well.

Reference

Lowe CJ, Hall PA et al (2014). The Effects Of Continous Theta Burst Stimulation To The Left Dorsolateral Prefrontal Cortex On Executive Function, Food Cravings And Snack Consumption. Psych Med. Sep 76(7): 503-511. DOI: 1097/PSY.0000000000000090.