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Here are a list of sources that we used if you wish to do more reserach:

-  Contemporary Clinical Trials Communications 25 (2022) 100766

- A Narrative Review on Intermittent Fasting as an Approachable Measure for Weight Reduction and Obesity Management Author: Raghav Janaswamy , Pallavi Yelne

-  Effects of Different Types of Intermittent Fasting Interventions on Metabolic Health in Healthy Individuals (EDIF): A Randomised Trial with a Controlled-Run in Phase

-Exercise Training and Fasting: Current Insights: Open Access Journal of Sports Medicine

Transcript Below:

00:00-00:05
Welcome back, everybody, to another deep dive, this time into the world of intermittent fasting.


00:06-00:07
Fasting.


00:07-00:08
Fasting, yeah.


00:08-00:08
Yeah.


00:08-00:18
We've got a really interesting collection of research papers on this, and I know this is a topic that a lot of people are curious about, and I think we've got some stuff here that'll really help clarify some things.


00:19-00:20
Yeah, definitely.


00:20-00:22
So when we talk about intermittent fasting, IF.


00:23-00:23
IF.


00:24-00:24
Yeah.


00:25-00:28
It's not so much about what you eat, like a lot of other diets.


00:29-00:30
It's more about when you eat.


00:30-00:32
Yeah, that's a good distinction.


00:32-00:34
I think that gets missed a lot.


00:34-00:34
Right.


00:35-00:37
It's not saying don't eat carbs or don't eat fat.


00:38-00:43
It's more about strategically cycling between eating and not eating.


00:43-00:44
Exactly.


00:44-00:47
And there are a number of different approaches to it that we can look at.


00:47-00:53
And when we look at those approaches, what are some of the most common ways that people are doing IF these days?


00:53-00:57
Well, probably the most popular one that you've probably heard about is what's called time-restricted feeding.


00:58-00:58
Okay.


00:58-01:00
En dat would be like the 168 method.


01:01-01:04
Where you fast for 16 hours and you have an 8-hour eating window.


01:05-01:06
Yeah, that's the one I hear about the most.


01:06-01:08
Yeah, that's a very popular one.


01:08-01:10
There's also alternate day fasting.


01:10-01:11
Okay.


01:11-01:14
Where you would alternate between a day of eating normally.


01:15-01:18
And a day of either fasting completely or severely restricting your calories.


01:19-01:19
I see.


01:19-01:21
And then there's also something called periodic fasting.


01:22-01:24
Which involves longer fasting periods.


01:25-01:25
Longer?


01:25-01:28
Yeah, maybe a couple of days at a time spaced out throughout the month.


01:29-01:29
Okay, interesting.


01:29-01:33
So you've got like a whole spectrum of different ways to approach this.


01:33-01:33
Right.


01:33-01:39
One of the studies you highlighted I thought was really fascinating was this one that's focusing specifically on a Lebanese community.


01:39-01:39
Yes.


01:39-01:41
And the impact of time-restricted feeding.


01:42-01:43
This one is really interesting.


01:43-01:50
And what they're doing is they're tracking a number of important markers over a 12-week period for these individuals.


01:51-01:51
Okay.


01:51-01:54
And one of the key markers they're looking at is something called VO2 max.


01:55-01:58
VO2 max. Now, just for our listener, can you just quickly define that?


01:58-02:04
Sure. VO2 max is essentially a measure of how efficiently your body uses oxygen during exercise.


02:04-02:04
Oh, I see.


02:05-02:07
So, it's a good indicator of your cardiovascular fitness.


02:08-02:17
Okay. So, theoretically, then, if EOF can have a positive impact on VO2 max, it could mean you could work out harder and for longer?


02:17-02:18
Potentially, yes.


02:18-02:21
Interesting. Okay. So, that's one of the things they're looking at. What else are they measuring in this study?


02:22-02:32
Well, in addition to the VO2 mix, they're also looking at things like body composition, changes in cholesterol levels, blood sugar regulation. They're even looking at sleep patterns.


02:32-02:36
So, you know, we often hear about IF in the context of weight loss.


02:36-02:37
Right.


02:37-02:41
But you're looking at research here that suggests that it might have benefits far beyond that.


02:42-02:46
Exactly. It's not just about weight loss. There could be a whole range of health benefits that we're just beginning to understand.


02:46-02:55
Right. And what's really fascinating, I think, is some of the physiological changes that are actually happening in the body during a fast.


02:55-02:55
Right.


02:56-02:59
Can you sort of walk us through, like, what's going on at a fundamental level?


03:00-03:04
Sure. So, when you fast, your body essentially goes through what we call a metabolic switch.


03:04-03:04
Okay.


03:04-03:10
So, it shifts from using glucose as its primary fuel source to burning fat.


03:11-03:14
Oh, I see. So, it's like flipping a switch from, you know, burning wood to burning coal.


03:14-03:21
Yeah, that's a great analogy. And this metabolic switch is driven by some key hormonal changes that happen in your body.


03:21-03:21
Such as?


03:21-03:32
Well, insulin levels decrease when you fast, while adrenaline and cortisol levels rise, and these hormonal shifts directly impact how your body responds to exercise.


03:32-03:40
Okay, so walk me through that. How do these hormonal changes actually affect the whole fat burning and exercise equation?


03:40-03:47
Well, when insulin levels drop, your body becomes less likely to store fat and more likely to start looking for alternative fuel sources.


03:48-03:54
And then as adrenaline and cortisol rise, they actually signal to your body to start breaking down fat for energy.


03:54-03:55
Interesting.


03:55-03:59
So this is why a lot of people report feeling more energized during their workouts while fasting.


04:00-04:01
I can see how that would make a difference.


04:01-04:10
Yeah. You mentioned a study that specifically explored whether training in a fasted state could enhance endurance performance.


04:11-04:11
Yes.


04:11-04:14
I found that really interesting. What were some of the findings of that research?


04:15-04:26
Well, this study focused on athletes, and it found that exercising in a fasted state, as opposed to after eating, might lead to something called increased fat oxidation.


04:27-04:29
And can you just quickly explain what that is for our listener?


04:29-04:35
Sure. Fat oxidation is essentially your body's ability to utilize fat as fuel during exercise.


04:36-04:36
Okay.


04:36-04:43
So the study suggested that training in a fasted state could enhance this process, potentially leading to improvements in endurance performance over time.


04:43-04:51
So theoretically, if someone's training for like a marathon or something like that, working on a fasted state could help them, you know, go the distance.


04:52-04:58
Potentially, yeah. But of course, more research is needed to fully understand this complex interplay between IF and endurance.


04:58-04:58
Right.


04:58-05:00
It's a promising area of research for sure.


05:00-05:09
Okay. Now, before we dive too deeply into the specifics of IF and different exercise types, I want to kind of step back and look at those wider health benefits that you mentioned.


05:09-05:10
Sure.


05:10-05:15
You said there's evidence to suggest that IF can have a positive impact on a number of health markers.


05:16-05:16
Yes.


05:16-05:17
Can you talk about some of that?


05:17-05:23
Yeah. A lot of this comes down to the cellular and metabolic changes that happen when you fast.


05:23-05:24
Right.


05:24-05:32
For example, you tend to see improvements in insulin sensitivity, which is crucial for regulating blood sugar levels and preventing type 2 diabetes.


05:32-05:34
And that's a huge one these days, right?


05:34-05:36
It is. It's a big concern.


05:36-05:37
Yeah, for sure.


05:38-05:41
What are some other areas where we're seeing positive impacts from IF?


05:42-05:47
Well, there's also some promising research showing that IF might have beneficial effects on cardiovascular health.


05:48-05:56
For instance, one study found that participants who practiced intermittent fasting experienced improvements in both their cholesterol levels and blood pressure readings.


05:57-05:58
Wow, that's impressive.


05:58-05:59
Yeah, it's promising.


05:59-06:06
Yeah. So we're painting a pretty rosy picture here. Are there any potential downsides or challenges to IF?


06:07-06:09
Well, of course, like anything, there are always two sides to the coin.


06:10-06:10
Sure.


06:10-06:19
One study highlighted some potential concerns suggesting that IF could promote erratic eating patterns and even potentially lead to hormonal disruptions.


06:20-06:22
So it's not a perfect solution for everyone.


06:22-06:26
Exactly. And it's important to highlight that much of the research on IF is still in its early stages.


06:27-06:34
We need more research to gain a complete understanding of the long-term effects, especially on areas like cardiovascular health.


06:34-06:40
And of course IF is not a one size fits all approach, individual responses can vary widely.

06:41-06:45
Yeah, and speaking of individual needs, you emphasise the importance of personalised approaches 


06:45-06:46
Yes.


06:46-06:47
Especially for people with disabilities.

06:48-06:48
Absolutely.


06:48-06:49
Can you elaborate on that a little bit?


06:49-06:55
Unfortunately, there's limited research on how IFF and exercise specifically affect individuals with disabilities.

06:56-06:56
Okay.


06:56-07:08
So it's crucial for anyone with a disability who's considering IAF to consult with a healthcare professional to determine if it's appropriate for them and to discuss any potential modifications or adaptations that might be necessary.


07:09-07:11
Right, so personalized guidance is really essential here.


07:12-07:14
Absolutely, just like with any other lifestyle change.


07:14-07:17
Okay, so let's just quickly recap what we've learned so far.


07:17-07:17
Okay.


07:18-07:21
We've established that IAF is about more than just weight loss.


07:21-07:21
Right.


07:22-07:30
It has the potential to offer a range of health benefits, from improved insulin sensitivity to potentially enhancing athletic performance.


07:31-07:33
Right. But it's not without its potential challenges.


07:33-07:38
Sticking to an IF plan can be difficult, and there are potential side effects to consider.


07:39-07:46
And as we've discussed, it's definitely not a one-size-fits-all approach. Individual responses can vary, so personalized guidance is key.


07:47-07:54
Excellent points. Now, with that in mind, let's delve into the fascinating interplay between IF and different types of exercise.


07:54-07:54
Okay.


07:55-07:59
We've touched on its potential to boost endurance, but what about activities like strength training?


08:00-08:03
That's a great question, and it's one that researchers are actively investigating.


08:03-08:08
A few studies you shared examine the effects of combining IF with both endurance and resistance training.


08:09-08:09
Okay.


08:09-08:11
And the results are quite interesting.


08:11-08:13
All right, so let's break it down for our listener.


08:13-08:15
What are the key takeaways from these studies?


08:16-08:20
What should people be aware of when considering combining IF with their workout routine?


08:21-08:25
Well, it's important to remember that the research on IF and exercise is still evolving.


08:26-08:30
We don't have all the answers yet, but what we do know is pretty intriguing.


08:30-08:38
Some studies suggest that exercising in a fasted state, especially when it comes to endurance training, could lead to greater adaptations in the body.


08:38-08:43
Okay, so working out on an empty stomach might actually help someone get more out of their endurance training.


08:44-08:45
What kind of adaptations are we talking about?


08:45-08:54
Well, as we talked about earlier, exercising in a fasted state could enhance the body's ability to use fat as fuel, which could potentially improve endurance over time.


08:55-08:58
Think of it as training your body to become more efficient at burning fat.


08:58-09:05
But what about those of us who are hitting the gym to build muscle? Does IF have any impact on muscle growth?


09:05-09:10
That's where things get a bit more nuanced. The research on IF and strength training is a bit mixed.


09:11-09:18
Some studies have found that as long as your protein intake is adequate, IF doesn't seem to negatively impact muscle growth.


09:18-09:24
However, other research indicates that there might be a slight advantage to training in a fed state when it comes to building muscle mass.


09:24-09:30
So, if someone is really focused on packing on muscle, they might be better off hitting the weights after they've had a meal?


09:31-09:34
That's a possibility, but it's not a hard and fast rule.


09:34-09:43
More research is needed to provide a definitive answer, and of course it's important to consider individual factors like training experience intensity and overall diet.


09:43-09:45
It's not just about when you eat, but what you eat as well.


09:46-09:52
You mentioned the timing of exercise earlier. Does it make a difference when you exercise in relation to those fasting and eating windows?


09:53-10:03
There's some interesting research on this. One study found that exercising in the afternoon during Ramadan, which is a period of daily fasting observed by Muslims, might actually lead to enhanced aerobic performance.


10:04-10:05
That's surprising. Why would that be?


10:06-10:14
The researchers believe this might be due to factors like muscle temperature and glycogen mobilization being more favorable in the afternoon during this period of fasting.


10:14-10:20
So if you're following an IF protocol, it might be worth experimenting with different workout times to see what works best for your body.


10:21-10:24
Absolutely. It's all about finding what works best for you.


10:24-10:28
Your body and your fitness goals. What works for one person might not work for another.


10:28-10:31
All this talk about the potential benefits of IF is exciting.


10:32-10:37
But we have to address the elephant in the room, actually sticking to an IF plan.


10:38-10:44
Is it realistic for most people? I mean, I love my morning coffee, and the thought of skipping it is a bit daunting.


10:44-10:50
You bring up a crucial point. Adherence is a major factor with any lifestyle change, and IF is no exception.


10:51-10:57
One study you provided explored IF adherence in healthy individuals and found, not surprisingly, that it was challenging.


10:57-11:03
So even for people who are generally health-conscious and motivated, IF can be tough to maintain over the long term.


11:03-11:10
It can be life happens, social events, cravings, busy schedules, and sometimes you just really want that midnight snack.


11:10-11:12
And then there are those potential side effects we mentioned earlier.


11:13-11:17
Some people experience headaches, fatigue, or mood swings, especially in the beginning.


11:18-11:20
So it's not a magic bullet, and it's definitely not for everyone.


11:20-11:32
Exactly, and that's why it's so important to listen to your body and work with a healthcare professional if you're considering trying IF, they can help you determine if it's a good fit for you and help you create a plan that's both safe and sustainable.


11:33-11:41
That's a great point. And before we wrap things up, I want to circle back to something we touched on earlier, the lack of research on IF and exercise in individuals with disabilities.


11:42-11:44
You mentioned it's an area that needs more attention, right?


11:44-11:47
Unfortunately, yes. There's a real need for more research in this area.


11:48-11:54
Individuals with disabilities are often underrepresented in health and fitness research in general, and IF is no exception.


11:54-11:59
It's important to remember that everyone's body is different, and what works for one person may not work for another.


11:59-12:04
This is especially true for people with disabilities who may have unique needs and considerations.


12:05-12:09
So if someone with a disability is thinking about trying IF, what steps should they take?


12:10-12:16
The most important thing is to consult with their doctor or a qualified healthcare provider who understands their specific condition.


12:16-12:24
IF might not be appropriate for every individual with a disability, and certain adaptations to the fasting protocols or exercise routines might be necessary.


12:26-12:35
For example, someone with diabetes might need to adjust their medication schedule if they're fasting, or someone with a physical disability might need to modify their workouts to accommodate their limitations.


12:36-12:48
So, just like with any lifestyle change, personalized approaches are essential. It's about understanding the potential benefits and risks, and then tailoring a plan that aligns with their individual needs and goals.


12:48-12:53
Precisely. There's no one-size-fits-all approach to health and wellness, and that includes IF.


12:53-13:10
This has been a truly fascinating deep dive. We've covered a lot of ground from the basic principles of IF to the potential benefits and challenges. We've talked about how it might impact weight loss, athletic performance, and even chronic disease prevention. But before we sign off, I want to leave our listener with one final thought-provoking question.


13:11-13:26
We've talked about IF's impact on weight exercise overall health, but what about its potential to influence how we age? You highlighted research suggesting that IF might actually influence cellular processes that play a role in aging. That's fascinating.


13:26-13:40
It is, and it opens up a whole new way of thinking about the potential of IF. You see some of the research suggests that IF's effects go beyond those short-term metabolic changes. It might actually influence cellular processes that play a role in how we age.


13:40-13:45
Hold on. Are you suggesting that IF could be a key to slowing down the aging process? That's a bold idea.


13:45-13:50
It is bold, and it's important to emphasize that this is still an active area of research. We don't have all the answers yet.


13:51-13:57
But the preliminary findings are intriguing. One of the studies you provided discussed a cellular process called autophagy.


13:58-14:05
Autophagy. I'm not familiar with it. Can you explain what it is?


14:05-14:15
Sure. Think of autophagy as your body's way of cleaning house at the cellular level. It's like a built-in recycling system that removes damaged cell components and helps cells regenerate. And some studies suggest that IF can actually stimulate this process.


14:16-14:21
So IF could be giving our cells a little boost, helping them stay younger and healthier for longer.


14:21-14:35
That's amazing. It is a fascinating area of research, and it raises many questions. Imagine a future where personalized IF protocols tailored to individual needs and genetic predispositions could play a role in promoting healthy aging.


14:36-14:38
That's a future I think many of us would be interested in.


14:38-14:42
So for our listener who's been on this deep dive with us, what's the key takeaway here?


14:42-14:45
What should they be considering as they process all this information?


14:46-14:48
I think the biggest takeaway is that knowledge is power.


14:49-14:57
By understanding the science behind the potential benefits and the challenges, you're in a much better position to make informed choices about your health and well-being.


14:58-15:00
That's a great point. It's about empowering yourself to make the best decisions for you.


15:01-15:07
consult with your healthcare provider, consider your personal goals, and don't be afraid to experiment to find what works best for you.


15:08-15:13
And who knows, maybe IEF will indeed hold a key to a longer and healthier future for us all.


15:13-15:16
Thanks for joining us for this deep dive. We'll catch you next time.