Curious about the benefits of fasting for runners? Then you’re in the right place.
From the casual joggers to the marathon veterans, many are now dabbling in various forms of fasting – be it intermittent fasting, time-restricted eating, or even those longer fasts.
But let’s get real – what’s the actual deal with fasting and running? Are we talking about a game-changing strategy or just another trend? That’s exactly what I’m diving into today.
In this article, I’m delving into the ins and outs of fasting for runners, cutting through the noise to find the facts. We’ll explore how fasting might just turn the body into a more efficient machine, burning fat for fuel and potentially boosting endurance.
Sounds like a great deal?
Then let’s get started.
A Personal Journey into Fasting
Before we dive into the science, let me share a personal story. As an avid runner, I’ve always been curious about ways to improve my performance. A few years ago, I stumbled upon intermittent fasting. It seemed intriguing, but I was skeptical. Would fasting really make a difference in my running journey?
I decided to give it a try, starting with the 16/8 method – fasting for 16 hours and eating within an 8-hour window. The first few days were a challenge. I’d feel those hunger pangs during my morning runs.
But as I persisted, something incredible happened.
Gradually, I noticed a shift in how I felt during my runs. My body seemed to adapt to using stored fats for energy, and those long-distance runs became more manageable. It was like my body had tapped into a hidden reservoir of energy that I never knew existed. I also lost some stubborn weight along the way—which was the reason I got on the fast in the first place.
I cannot promise you similar results, but at least, I believe that fasting is something worth trying.
Understanding Fasting
Fasting, more than just skipping a meal, is a deliberate choice to refrain from caloric intake for a specific time. It’s like hitting a ‘reset’ button for your body, and it brings about some fascinating changes to your metabolism and hormone levels.
Overall, there are three types of fasting protocols to choose from:
- Intermittent Fasting (IF): Cycling between eating and fasting periods, like the 16/8 or 5:2 methods.
- Time-Restricted Eating (TRE): Eating within a specific daily window.
- Prolonged Fasting: Fasting for extended periods, such as 24 hours or more.
The Many Phases Of Fasting
Understanding the feeding phase and the transition into fasting is crucial for anyone interested in fasting, whether for health, weight loss, or other reasons.
Let’s break down what happens in your body during these phases:
Feeding Phase (Anabolic Growth Phase)
Your body uses the nutrients from your last meal, with insulin playing a key role in managing glucose levels and storing excess energy. Excess glucose is stored in your liver and muscles as glycogen or converted to triglycerides and stored as fat.
Depending on your meal’s size and content, this phase typically lasts 4 to 6 hours after eating.
Early Fasting State (4 to 18 Hours After Last Meal)
As no new carbs are consumed, insulin levels decrease, leading to a reduction in glucose storage and an increase in fat breakdown.
Leptin levels (which signal fullness) drop, and ghrelin levels (which signal hunger) increase.
Around 8 hours in, your liver depletes its glucose reserves, and your body starts producing glucose from other sources. This is what’s known as Gluconeogenesis.
Your body initially uses muscle and liver glycogen for energy, then starts lipolysis to break down fats into triglyceride
About 18 To 48 Hours Into A fast
Around 18 to 48 hours into fasting, you enter a more intense phase. Glycogen stores are depleted, and your body relies more on protein and fat for energy.
This stage sees a significant shift towards ketosis, where your body begins to burn fat as its primary energy source. The production of ketones becomes more prominent, offering an alternative fuel for your brain and other tissues.
Physical and mental changes can be noticed as you fully enter ketosis. This state is often characterized by reduced hunger and increased energy levels, making it a coveted phase in the fasting and keto communities.
Prolonged Fasting: Beyond 48 Hours
Fasting for over 48 hours falls into the category of prolonged fasting. Here, your body relies heavily on ketones and muscle protein for energy.
During prolonged fasting, your body is in a deep state of ketosis, efficiently using fat reserves as the main energy source.
It’s crucial to approach prolonged fasting with caution and planning. Selecting a specific start time and taking necessary precautions during the fast is advisable.
However, fasting for such extended periods is not recommended for everyone and should only be undertaken under medical supervision.
The Benefits of Fasting
Intermittent fasting has gathered so much steam over the past few years thanks to the many health benefits such as improved insulin resistance, weight loss, cellular repair, weight loss, and mental clarity.
Let’s jog through a few of these perks, shall we?
Fat Loss:
Struggling to shed those stubborn pounds? Fasting might be your secret weapon. By creating a calorie deficit, it can kickstart fat loss. And for us runners, staying light on our feet is key to clocking better times and going the distance.
Maintaining Muscle:
Intermittent fasting helps cut down fat without eating into your muscle mass, research shows. That means more power for each stride!
Shedding Pounds with a Timer:
Forget complex diets; fasting is like hitting the fast-forward button on weight loss. When you fast, your body switches from using glucose to burning fat. It’s like telling your body, “Hey, let’s use those reserves!” And the science backs this up – research shows fasting ramps up metabolism and targets fat loss.
Ketosis, But Quicker:
If you’re riding the keto wave, fasting can help you reach ketosis faster. It’s like giving your body a head start in the fat-burning race.
Aging Slowed Down:
Imagine if eating (or not eating) could help you live longer. Studies suggest that fasting reduces certain aging factors. It’s like pressing pause on the aging remote.
A Shield Against Diabetes:
Fasting isn’t just about weight; it also helps regulate blood sugar and insulin levels. This could mean a lower risk of type 2 diabetes, a huge win for your long-term health.
For more on the benefits of fasting, check the following research papers:
- INTERMITTENT FASTING AND HUMAN METABOLIC HEALTH
- Intermittent fasting: The positive news continues
- Research review shows intermittent fasting works for weight loss, health changes
- Intermittent fasting: eating by the clock for health and exercise performance
- Intermittent fasting: Is it all it’s cracked up to be?
- Benefits of Intermittent Fasting: A Systematic Review of Randomized Clinical Trials
This is great and all, but what about runners? Does intermittent fasting help? Let’s check them
What Are The Health Benefits Of Intermittent Fasting For Runners?
Runners, let’s dive into the exciting world of intermittent fasting (IF) and how it might just be the secret ingredient to boosting your performance!
Studies, like one from the British Journal of Nutrition, highlight how training in a fasted state amps up fat burning, crucial for those long runs where you’re digging deep into your energy reserves.
A piece from the Journal of Applied Physiology throws a spotlight on runners who trained without breakfast. Guess what? They showed more endurance gains than those who fueled up pre-run. It’s like giving your stamina an invisible boost!
Recovery and VO2 Max: A Winning Combo
IF isn’t just about endurance. It’s about bouncing back faster. Improved nutrient absorption and reduced inflammation mean you’re ready to hit the track again sooner.
According to Nutrients journal, IF can trim down your body fat and, wait for it, potentially up your V02 max. That’s like upgrading your engine for better performance.
Performance and Health – A Dual Track
Sure, intermittent fasting health benefits are well-documented in general, but for runners? It’s about fine-tuning your body composition and keeping those inflammatory responses and immune system in top shape.
But, Is It for Every Runner?
If you’re eyeing a podium finish, jumping into IF might throw a wrench in your training, especially if you’re not accustomed to fasting. However, if your goals lean more towards weight loss and body composition, IF could be a great ally.
Take a cue from elite cyclists. One study showed that with an 8-hour eating window, they shed weight, improved body composition, and maintained performance over a rigorous 4-week training period. Plus, they saw a spike in power output relative to body weight – a big win for any runner.
It’s not just about fasting; it’s about maintaining a balance. Research, including studies on athletes fasting during Ramadan, shows that as long as you manage your overall nutrition, sleep, and training load, performance doesn’t have to take a hit.
The Downsides Of Intermittent Fasting In Runners
So, you’ve heard about intermittent fasting (IF) and its potential perks, right? But let’s hit the brakes for a sec and talk about the flip side. Yes, IF isn’t a one-size-fits-all, and it’s super important to know what you might be signing up for.
Hunger Games: The Real Challenge
Picture this: going hours without a snack or a meal. Sounds tough, huh? That’s because, in our comfy world, we’re usually just a fridge away from our next bite. Intermittent fasting asks you to break that habit, which can be a real test of willpower.
Runners, Beware of Dizzy Spells
Imagine lacing up for a long, intense run at the tail-end of your fast. Not the best idea. You might end up feeling like you’re running on fumes, literally. If you’re new to the fasting track, start with easy jogs. Safety first, always!
Performance Pitfalls: Not Running on Full
A study in the Journal of Sports Medicine points out a crucial fact – there’s no solid proof that fasting boosts performance for endurance athletes. In fact, running on an empty stomach could mean your usual zippy self is now running in slow-mo.
Is IF a Runner’s Friend? Well, It’s Complicated.
IF can be a hit or miss, depending on tons of factors like your running routine, body type, and even your lifestyle. It’s like trying to wear someone else’s running shoes – not always a great fit.
Who Should Definitely Not Fast?
If you struggle to keep weight on, are underweight, pregnant or breastfeeding, have a history of eating disorders, or battle chronic conditions like high blood pressure or diabetes, then IF could be more of a foe than a friend.
In a nutshell, IF isn’t a magic pill, especially for us runners. It’s crucial to weigh the pros and cons and see how it fits into your running and life equation. And hey, always good to chat with a health pro before jumping on the IF bandwagon.
Keep running and stay healthy!