When to Exercise and Does it Matter?

00:00:00: Diabetes Insights, Breakthroughs and Innovators.

00:00:04: The EASD TV podcast from the annual meeting of the European Association for the Study.

00:00:20: And it was a session that was packed out, not just because of the great science but also because people are so personally invested in knowing when how and at what time they should exercise.

00:00:35: So I'm delighted we've got Haroun van der Velder here with us... ...and you were involved in the exercise bit for this session!

00:00:45: When shall we exercise?

00:00:48: Well, that's the million-dollar question indeed.

00:00:51: Which I hope you're going to answer!

00:00:53: Yeah well... The thing is we are not hundred percent certain.

00:00:59: so there have been many studies ongoing for past couple of years looking into specifically the timing of exercise.

00:01:06: So does it matter if you exercise in a morning afternoon or evening?

00:01:10: To lower heart risk, diabetes risk and so on.

00:01:14: And what we've learned so far is that there are large discrepancies between the studies and between results.

00:01:20: So some study suggests to mitigate heart failure or lower your risk for cardiovascular disease, you should be most active in the morning while other studies have suggested it's a more active afternoon or evening.

00:01:34: It all over the place?

00:01:36: Most of them get consistent if you start looking at one specific disease, so for instance let's take diabetes since we're at the EASD.

00:01:48: For diabetes it is much more consistent and most of studies looking at glycemic control or type two diabetes risk look at exercise not as much total physical activity.

00:02:01: but Exercise means physical activities which increases your heart rate, it increases your respiration.

00:02:09: It could be brisk walking or cycling in the Netherlands but if you look at those things there is clear and consistent relation between activity later on a day and lower diabetes risk and better glycemic control.

00:02:24: When

00:02:24: are we talking about

00:02:30: later?

00:02:34: starting in the late morning and ending at some points, early evening.

00:02:42: There are so many things going on your body that have to do with circadian rhythms.

00:02:47: That's why we started looking into this whole concept of exercise timing.

00:02:52: For your circadian rhythm light exposure is the most important trigger but you're also reacts to external triggers like exercise, but also diet temperature exposure sleep.

00:03:07: so your timing of sleep and people also have a preference for sleep timings.

00:03:11: So if you really are morning person...

00:03:13: Oh yes I was going to ask whether it depends on chronotype?

00:03:16: Whether you're an owl or a lark!

00:03:20: There were some studies that looked into this.

00:03:24: I think it's a really important question, so is there an interaction between your chronotype and exercise preference?

00:03:32: And some studies do suggest that people for instance are characterising themselves as evening type.

00:03:38: If they exercise in the morning its less advantageous than those who consider themselfs to be morning person For example.

00:03:47: So just probably some interaction going on.

00:03:50: but theres definitely more research needed into this specific area and also in the interaction between exercise timing, but also meal-timing.

00:03:59: So all of these things are cues to your body... ...in terms of release of hormones?

00:04:07: Yes so basically our body is entrained by our central clock which is in our hypothalamus And that mainly receives its feedback information from light exposure.

00:04:19: Basically all our organs have a clock themselves The central clock in your hypothalamus, it interacts with your peripheral clocks.

00:04:30: But specifically those peripheral clocks they also receive their information from your behavior.

00:04:35: and well a couple of hundred years ago that was no problem.

00:04:38: But nowadays, in our Western modern society you get light exposure.

00:04:42: Twenty-four hours per day there's food available twenty four hours a day and You can go to gyms twenty for hours of the day.

00:04:49: So these signals that you receive your peripheral clocks They don't need to align with your central clock anymore.

00:04:57: And what we think What is often referred to as circadian misalignment or circadian disruption?

00:05:04: In the end it may lead to metabolic consequences like type two diabetes.

00:05:08: So if you exercise more in line with what the nature is telling us, that should help to restore our circadian rhythm.

00:05:17: It has implications for I guess particularly for night shift workers?

00:05:23: Oh yes!

00:05:25: That's a very difficult sub-population because it's very well documented and people who work at night shifts do this for longer periods of time clearly at the increased risk for all sorts of metabolic diseases.

00:05:43: In part, it's probably also because they adopt their lifestyle to that night shift work and especially eating behavior during a night shift is quite unhealthy but still basically they experience chronic jet lags all the time in end year after year piles up and develops metabolic problems.

00:06:06: Is consistency also very important?

00:06:09: In other words, that if you exercise let's say in the early afternoon.

00:06:16: That is always a time within reason that you exercise

00:06:22: because

00:06:22: it does consistancy confer a stronger cue to your body.

00:06:28: Well thats'a good question and I haven't looked into this myself but i'm aware of some studies pattern throughout the week, for instance people that engage like you mentioned in activities basically every day at the same time.

00:06:42: There's not much... Not that strong evidence of consistency.

00:06:45: is it's more important to get your minutes a couple hours of exercise and probably better or maybe if later than any morning but Just getting those minutes in, get that exercise done.

00:06:59: That's the most important

00:07:00: thing.

00:07:00: Even after all your work you've done... ...the message is better to exercise than not to exercise.

00:07:07: and if you are going to exercise... ...better for people living with diabetes from say noon onwards up to about six then do it first thing morning?

00:07:19: With some caution.

00:07:21: yes I think what we're where right now But I really think we need to look more into the whole interaction with sleep and chronotype, timing of meals.

00:07:33: And really look in specific subpopulation.

00:07:36: so is it important for everyone?

00:07:37: Is it important people living with diabetes or are at increased risk for diabetes?

00:07:43: So that's stuff we're looking right now.

00:07:46: In next couple years i hope can be more specific.

00:07:51: Were the questions particularly interesting?

00:07:53: Because I imagine that lots of these sessions, there were some really interesting questions at the end.

00:07:58: But I imagined a lot people asking question which was about themselves!

00:08:05: Yes... Of course this topic is relevant for everyone and most people are aware exercise is important especially with busy life And they want to exercise.

00:08:20: just have to find a time, two exercises for lots of people myself included.

00:08:25: Sometimes this is the morning and if that's the only time in week you can perform exercise.

00:08:30: please do it!

00:08:32: And some questions were mostly related to individual cases but its really hard.

00:08:41: so I work with population studies observational studies.

00:08:45: It was really hard from there to individualised advice.

00:08:50: So we really need smaller studies, intervention studies that target specific individuals or specific subpopulations.

00:08:58: Change exercise behaviours see if the change in exercise actually does influence your metabolic health and I think will improve our understanding of what do you have to advise who?

00:09:15: It's a fascinating area.

00:09:16: thank-you so much for coming into talk about it.

00:09:18: Thank-you very much.

00:09:20: Thank you for joining us on the podcast of The European Association For The Study Of Diabetes.

00:09:26: We hope you enjoyed today's insights!

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