Dr. Umar Toseeb Hello, welcome to the Papers Podcast series for the Association for Child and Adolescent Mental Health, or ACAMH for short. I’m Umar Toseeb, a Professor at the University of York. In this series, we speak to authors of papers published in one of ACAMH’s three journals. These are the Journal of Child Psychology and Psychiatry, commonly known as JCPP, the Child and Adolescent Mental Health, known as CAMH, and JCPP Advances. Today, I’m talking with Stone Hsieh, Senior Lecturer in the Department of Psychology, Kingston University London. Stone is the Lead Author of a JCPP editorial perspective called “Healthy Body – Healthy Mind? Does Exercise Benefit People with Attention-Deficit/Hyperactivity Disorder?” This editorial will be the focus of today’s podcast. If you’re a fan of our Papers Podcast series, please subscribe on your preferred streaming platform, let us know how we did, with a rating or review, and do share with your friends and colleagues. Stone, thank you so much for joining me. Can you start with an introduction about who you are and what you do? Shu-Shih (Stone) Hsieh First of all, thank you for having me. Very happy to be here and I’m Stone from Kingston, and I was actually originated from Taiwan. Before I jump into my current research, I was actually train in exercise physiology, but later, I was fascinated by how our brain connection and memory works and also, fascinated by how exercise can potentially optimise or maximise our brain function and cognition across the lifespan. So, I, kind of, changed my direction during my PhD, so I switched to focus on how exercise can benefit our cognition across the lifespan and my ongoing work – so, we, basically, used different cognitive and psychological measures, or psychological tools, to study how exercise can potentially modify or modulate our attention, cognition, memory, brain function, using different tools and neuroimaging measurements during the development, especially for neurodivergent children, such as children with ADHD and autism. Dr. Umar Toseeb And I can see from your publications that you’ve published lots on exercise and cognitive function, and you’ve talked about, just then, where you became interested in this during your PhD, but why specifically this line of research? Shu-Shih (Stone) Hsieh I think what drives me or motivates me and the most is that we know that exercise is beneficial for our brain and cognition. However, what we don’t know is what types of exercise, what modality of exercise and what about the frequency, duration of exercise? And we also know that one exercise cannot fit for everyone. So, I think what driven me in the, say, past ten years, is that I want to know how different exercise types, or modalities, or choices, are most effective or beneficial for different populations. I think another area that I have a strong interest in is that I also want to know what exercise is beneficial. So, that’s why I mentioned that in my research, I routinely incorporate different measurements, psychological, cognitive and neuroimaging tools. My overarching goal is that I want to know the best exercise options for different people, for everyone, and for different occasions, different needs. Dr. Umar Toseeb Fascinating. So, let’s turn to the editorial. Can you give us an overview, just a brief overview, of the editorial itself? Shu-Shih (Stone) Hsieh So, I think the editorial article mostly surrounds the topic of exercise and ADHD. Also, another focus is that I also discuss, as a Researcher, how we can move the research area further. So, I think at the beginning, I briefly summarised how exercise may affect deficits in cognition in young people with ADHD and then, secondly, I offer some recommendations based on the literature on experiences and emphasise that we need more research and focus on the brain mechanisms, or we say – we call neural markers that may drive the effects of exercise on ADHD. And also important is that we should trying to see whether or not changes in these brain mechanisms are intercorrelated with changes in ADHD symptoms. Because I think, at the end of the day, we need to know the brain mechanisms, what drive the effects of exercise, so that we can better tailor our exercise programme or our exercise intervention. Another emphasis of the article is that we should start just thinking about user perspective or user experience when we conceptualise or when we develop our exercise intervention, because at the end of the day, we want to promote and deliver our programme of intervention to the user, which should be the children and the parents. So, it’s vital for Researchers to start thinking about the perspective and feedback from our end user, children and parents, when we develop our intervention. And also, it would be vital to incorporate social support elements, such as support from parents, support from our peers, as part of the intervention programme. Lastly, I also emphasise the need to study and understand the long effect of exercise as compared to our clinical or usual treatments, because if we want to increase or enhance the clinical significance of exercise as a treatment plan or treatment option for ADHD, we need this type of research to compare the effects of exercise versus clinical treatments or medications, to increase the clinical significance. This needs to be done by more high quality and well designed clinical trials, for sure. Dr. Umar Toseeb Okay, excellent, and let’s unpack that a bit more. So, the first part of the editorial is about the treatments. So, what are some of… Shu-Shih (Stone) Hsieh Yeah. Dr. Umar Toseeb …the current treatments for ADHD and what are their limitations? Shu-Shih (Stone) Hsieh I think for now, the most common treatment plans for ADHD, the first is psychostimulant medication, the other one is behaviour treatment, but either one has its own limitation and shortages. For instance, for medication we know that firstly, the effects of medication is short-lived. So, many of the medication, the effect’s only sustained for four to six hours, or 12 hours. Another thing to note is that many of these medications has side effects. We’re collecting data for a project right now based on our own data. We learn that more than 50% of children who are taking ADHD medications are also experiencing theses side effects from medication, and this could be trouble sleeping, bad appetite and headache during the day, just to name a few. So, that’s why many parents, they are actually looking for some other, say, alternative behavioural treatments. Another type of treatment is behavioural treatment, such as cognitive behavioural therapy or parental education sessions, or psychosocial therapy. However, because these type of behavioural treatments they’re also effective, but these treatments has to be delivered by specialised Psychiatrist. So, I think this, kind of, further compromise the accessibility of the treatment. Right now, we know that despite medication and behavioural treatments are effective, but there are also many limitations. So, this, kind of, motivate and justify many Researchers, including myself, to looking for non-clinical behavioural treatments or interventions, such as exercise. Dr. Umar Toseeb Okay, now, let’s turn to exercise. What are the key findings from your own research, and others, on the impact of exercise on ADHD symptoms? Shu-Shih (Stone) Hsieh For now, the majority of research has shown that exercise can reduce dysfunctions in executive function. So, executive function is a higher-order cognition that involves in our goal-oriented behaviours. So that means, basically, your day-to-day behaviours are directed or dictated by exec functions, and research has showed that ADHD children have worse performance in exec function compared to their neurotypical peers. So, based on the current state of the research, we know that exercise has quite strong effect on executive function. So, in other words, for children with ADHD, exercise have the potential to reduce the dysfunction or impairments in their executive function. And also, some research demonstrate that even a single dose of exercise at a moderate intensity can actually reduce dysfunction in children with ADHD, but the effect is not very long, just a couple of hours after exercise. So, this is for exec function. For symptoms of ADHD, I think, for now, the body of literature is less limited. Different studies utilise different measurements for ADHD symptoms or behavioural symptoms. But I think for now, the consensus is that exercise can reduce inattention symptoms, but has less positive effects on symptoms such as hyperactivities and impulsivity. This is actually quite interesting, because this further drive us, or motivate us, to further looking at what make the differences between inattention and hyperactivities in terms of the selective effects of exercise. Dr. Umar Toseeb Okay, so just to make sure that I’ve understood that right. So, what you’re saying is there’s evidence to suggest that in children with ADHD, exercise, to some extent, helps to reduce the cognitive deficits that might be associated with the ADHD, such as executive function, but not necessarily the behavioural aspects of ADHD, such as hyperactivity? Shu-Shih (Stone) Hsieh Yeah, exactly, exactly. Dr. Umar Toseeb Okay, and I think one of the interesting things there is that some of the work that we’ve been doing in the general population, we’re finding that when we look at inattention and hyperactivity and see how it clusters with some cognitive functioning in the general population, it seems that inattention is more closely related to cognitive function, rather than hyperactivity. So, could that be maybe why the effects are shown for cognitive function and inattention, but not necessarily hyperactivity, because cognitive function, inattention are more closely related conceptually? Shu-Shih (Stone) Hsieh Personally, I think this might be the reason, because we know that executive functioning is highly correlated with attention, arousal and some higher-order cognition, but most of the focus on attention. And I think this where executive function plays the most vital role. But when it comes to hyperactivities or impulsivity, I think there are more brain mechanism underly hyperactivities or impulsivities. So, for instance, yeah, we know that there are other brain mechanisms, such as motivation, reward seeking, delay aversion, all these might be the factors affecting hyperactivities and impulsivities. And yeah, so this might be the reason that exercise shows less promising effects on hyperactivities and impulsivity, because based on the current state of the literature, I think the exercise intervention we have right now is not that effective for cognitive domains, such as motivation, sensation seeking and motivation. To solve this question or this limitation, we certainly need more research focusing on this, with other types of cognitive aspects. Dr. Umar Toseeb And when you were describing exercise, you mentioned ‘moderate exercise’. Can you just unpack a bit more about what the types of exercise are? Like, in the research with children with ADHD, what does ‘moderate’ mean and does it make a difference whether it’s group exercise, individual exercise, intensity and all of those kinds of things? Shu-Shih (Stone) Hsieh When we talk about moderate to vigorous exercise, we are actually talking about the intensity where you can chat and talk to your friends while you are exercising. If you start to feel like you are short of breath and you are – feel exhausted, this is vigorous exercise. So, in terms of brain function, cognition and attention, the most robust effects comes from moderate to vigorous intensity exercise. This is not just only for neurodivergent children. This is also for neurotypical children. This also applies to adults and the elderly. Right now, we know that aerobic-based exercise is most beneficial, because aerobic exercise can directly lead to structural and functional changes in our brain, such as our prefrontal cortex, such as hippocampus and it also can trigger greater connection between different cortical areas. So, all these are benefit for our cognition. But, in more recent years, Scientists start to also promote exercise that can challenge our cognition and finish at the same time. So, this could be football or tennis. As long as the exercise itself is capable to challenge our multitasking, attention, inhibition, decision-making, all these exercise are highly recommended, especially for children. Dr. Umar Toseeb Thank you, and let’s move onto to the mechanisms of action. So, what are some of the mechanisms through which exercise might benefit young people with ADHD? Shu-Shih (Stone) Hsieh From animal studies, right now, we know that exercise can induce higher secretion of key neurotransmitters in our brain, especially in our prefrontal cortex, which is a cortical region for decision-making, attention, higher-order cognitions. And when we – when it comes to one neurotransmitters, right now I think it is quite robust to say that exercise can trigger more secretion of dopamine and norepinephrine, and this actually similar to the effects of medication. From research, we also note that psychostimulant medication can also trigger increased secretion of dopamine and norepinephrine. So, I believe this is why Scientists start to thinking about, okay, maybe we can use exercise as a complementary treatment for ADHD, because exercise may have similar cortical effects as medications. When it comes to mechanisms, there are many different angles or perspective. So, if we use, say, neuroimaging as measurement, such as EEG, we know that exercise can lead to better attention engagement. That means our children can better recruit their neural resources when they need to pay attention and also, we know that from EEG, children can better inhibit their impulsive or autonomic behaviours. From functional MRI or more advanced neuroimaging tools, we know that after a single dose of exercise, the connectivity of between, say, the prefrontal cortex and other brain regions, such as ACC, parietal cortex, are becoming stronger, which is beneficial for attention, impulsivity and other cognitive aspects, such as cognitive flexibility. Dr. Umar Toseeb So, what you’re saying is the mechanisms through which exercise and medications work on ADHD symptoms and the associated cognitive deficits are similar and similar neurotransmitters are released in similar parts of the brain. Shu-Shih (Stone) Hsieh Hmmm. Dr. Umar Toseeb But is it to the same extent, or is one effect stronger than the other? Shu-Shih (Stone) Hsieh Actually, a very big question. I think for now, it is hard to say whether or not exercise can benefit our brain as effective as medication, because there’s not much evidence out there that directly compare exercise versus medication. So, when it comes to extent or level of, say – or the magnitude of effect, it’s hard to say. However, I think what is more important is that, as I mentioned, the effect of medication is not sustainable. Usually, the effects disappear in couple of hours. However, because exercise can lead to structural changes in our brain which cannot be achieved by medication. So, if we talk about, say, transient or shorter effects, it is hard to say. But if we’re thinking about the long-term adaptation induced by exercise versus medication, I think exercise would be a better option in terms of long-term structural changes. Dr. Umar Toseeb Okay, and then when we’re thinking about implementation in real world settings, what are the main challenges in translating exercise-based interventions from controlled research environments and, for example, you talked about animal studies, to the real world? Shu-Shih (Stone) Hsieh For now, laboratory-based study, we can only know the efficacy of exercise, because the environment is under control. In the birth study, we always have pre-visit instructions. We try to maximise the internal validity of our research and try to minimise any potential confounding factors. But I think for now, when it comes to effectiveness, acceptability or feasibility in the real world, we didn’t know much about this, but I think it would be important to note that young people with ADHD, they tend to have, say, lower self-esteem. Many of them have troubles in their relationships with their friends, their peers, their classmates and many of them also have inferior motor skills, such as hand-eye co-ordination, balance, etc., etc. All this may prevent them from participating in exercise, especially on a regular basis, because for them, it is very difficult to gradually build up their self-efficacy to build up a positive exercise environment for them. Or some of them might be able to participate, but many of them will not be able to participate at the level we want them to achieve. There’s always a gap between what we have found in the lab and what we can actually deliver in the real-world settings. I will recommend that we start from individualised exercise, because different young people may have different needs, different preferences, and I think at least at the very beginning, it would be important for them to gradually develop their self-efficacy, their self-esteem, their confidence in performing different type of exercise. Dr. Umar Toseeb Thank you, and I suppose my next question was going to be on customising interventions, but I think you’ve covered that quite well, because I think, like you say, young people with ADHD might have peer problems or friendship difficulties. Shu-Shih (Stone) Hsieh Yeah. Dr. Umar Toseeb There might be some research to support that. So, customising these interventions, exercise-based interventions, for people with ADHD is probably very important here. What kinds of factors might need to be considered during that customisation process? Shu-Shih (Stone) Hsieh I think there are a couple of key factors, such as the type of exercise they prefer, the ideal duration per exercise bout they prefer and the frequency of session per week. For instance, if you look at the literature, many papers will tell you that the most effective frequency for an exercise intervention is three to five times per week. If you actually ask children and parents whether or not you think you can participate in an exercise intervention for five times a week, many of them will tell you that it might be a bit difficult. And if you continue to ask them, “What is your prefer frequency of exercise per week?” they will tell you three times a week is their prefer frequency. Also, other factors to consider, what resources they need. Some parents, they might be having difficulties to encourage their children, because for children to keep participating in exercise, many of them also require company from their parents. So, many parents are struggling to find a way or solution, or effective way, to support their children, to perform the exercise with their children. So, some parents will specifically ask for resources that guide them to support their children to perform the exercise. And also, there are factors such as what are the motivators and barriers that may increase or prevent children and parents from participating in their intervention? All these are the key factors or elements that we need to consider. Dr. Umar Toseeb And I imagine there’ll be many parents out there and many listeners who would see this as an appealing intervention for ADHD. But before we can get to a point of this being a reasonable and valid and effective intervention, I imagine there are still lots of critical gaps in the current research on the relationship between exercise and ADHD that need to be addressed. What are those gaps and how strong is the evidence base for this? Shu-Shih (Stone) Hsieh As I mentioned in the editorial, I think there are a couple of gaps. I think the first gap is the mechanism. What are the brain mechanism that may try for explain the effects of exercise? Because right now, we only know that exercise benefits executive function, but for other brain mechanisms that may also underly ADHD, such as motivation, delay aversion, we don’t have much evidence on this. So, I think it will be vital to further clarify the brain mechanisms, because by better understanding the brain mechanisms, we can better tailor and develop our exercise intervention to optimise the effects. The second gap would be to consider user perspective. So, what I would suggest is that we can see exercise as a product and our users are parents and children. Our goal is to promote and to make sure that our product can be successfully deliver and promoted. We definitely need to know the feedback from children and parents. So, that’s why I emphasise a few times that when we develop exercise intervention, we need to consider user perspective. There are other gaps which is quite interesting to me is that there is not much evidence out there, but I think it would be interesting to explore how different subtypes of ADHD may affect the efficacy of exercise. We need to better understand the moderating role of the subtypes of ADHD. By better understanding this, we can offer or provide more precise exercise recommendation for different populations. Another gap I want to emphasise is that – to test the standalone effect of exercise versus medication, if our final goal is to say that exercise is indeed a behavioural and complementary treatment plan for ADHD. Dr. Umar Toseeb Thank you, and are there any upcoming studies or initiatives that you’re working on that you’d like to share with us? Shu-Shih (Stone) Hsieh For now, we are about to start an EEG study where we trying to look at different brain markers that may underly ADHD symptoms or capture ADHD symptoms. We will be using different neuroimaging tools to better understand the relationship between different cortical or brain markers in ADHD symptoms. We are also preparing an interventional study where we want to deliver eight weeks of exercise-based videogames to children and parents in the lab. And we want to see if our intervention can actually change impulsivity and hyperactivities and inattention, of course, in school aged children with ADHD. And also, a third initiative we are working on is currently, we are also inviting children with ADHD and parents to join us at Kingston to play and co-develop a PE – a physical education lesson with us. So, it is like a participatory research and co-design research. Dr. Umar Toseeb They sound very interesting. Very much looking forward to seeing the results of those. And then finally, what’s your take home message for our listeners? Shu-Shih (Stone) Hsieh I think this is not just for neurodivergent children and families. I think this applies to everyone. So, I think the key things is that there’s no perfect exercise or one exercise that fits for all. So, I think, in terms of improving our health and improving our attention, cognition and brain function, I think it would be vital to find an exercise that we love and can commit to consistently and stay with the exercise plan and try to make sure that your playing can become regular behaviour, and then, just experience the benefits of exercise. Dr. Umar Toseeb Thank you so much. A fantastic and fascinating conversation. For more details on the paper and Stone, please visit the ACAMH website, www.acamh.org, and Twitter @ACAMH. 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