Using Intermittent Fasting and High-Intensity Interval Training (HIIT) Exercise to Your Advantage

December 07, 2015 | 1,660 views

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In today’s world where convenience rules, we want results faster and efficient at the same time. But when it comes to our health and fitness goals, does this apply to selecting a diet?

Dr. Michael Mosley, a BBC journalist and author of "The Fast Diet: Lose Weight, Stay Healthy, and Live Longer with the Simple Secret of Intermittent Fasting," sought an answer to this question, and found it in the combination of intermittent fasting and high-intensity interval training (HIIT) exercises.

The Real Deal About Intermittent Fasting

At first, Mosley was overweight, and was diagnosed with diabetes and high cholesterol levels. His condition prompted him to constantly try new methods to live healthier, leading to his encounter with intermittent fasting – and from there he was able to regain his health back.

Intermittent fasting entails cutting your daily calorie intake in whole or in part, and instead switching to healthier types of food like:

  • High amounts of healthy fat-rich food like avocados, organic grass-fed butter, and coconut oil, to name a few, which should amount to 50 to 85 percent of your daily calories
  • Moderate portions (about 40 to 70 grams daily) of high-quality protein coming from organically raised, grass-fed, or pastured animals
  • Unrestricted amounts of organic and fresh vegetables

But while calorie restriction is vital, what sets intermittent fasting apart from other diet strategies is the timing of meals. It mimics our ancestors’ eating habits, who waited until food was available because of lack of access to it 24/7. By adapting this cycle of “feast and famine,” not only do you lose weight, but you also train your body to burn fat for fuel instead of glucose or sugar.

Advantages of Intermittent Fasting

Intermittent fasting is linked to a number of health benefits, such as eliminating your cravings for unhealthy foods.

Your brain can also benefit from intermittent fasting: you’re able to think clearer, get more stuff done, and be more efficient. It may also slow down your risk of cognitive function-related diseases, such as Alzheimer’s disease.

Dr. Mosley met up with Dr. Mark Mattson at the National Institutes of Aging, where the latter was conducting an experiment on mice that were genetically-engineered to develop Alzheimer’s disease or dementia in a year. Mattson placed these mice on an alternate-day fast, and the mice ended up developing the disease in two years instead, as opposed to a year. According to Mosley:

"When he (Mattson) looked into their brains, he discovered that the ones who had been on intermittent fasting diet have grown 40 percent new brain cells particularly in the area associated with memory. He identified this thing called BDNF or brain-derived neurotrophic factor, which seems to be driving those changes and also protecting the brains ..."

Results from this experiment showed that alternate-day fasting (with 600-calorie meals to boot) boosts BDNF from 50 to 400 percent, depending on the brain region, which then helps your body as it:

  • Activate brain stem cells to convert into neurons
  • Trigger other chemicals that promote neural health
  • Protect brain cells from changes associated with Alzheimer’s and Parkinson’s disease
  • Defend the neuro-motors (the most critical element in your muscle) from degradation in the neuro-muscular system where it expresses itself, allowing the muscles and the brain to work better for healthier brain tissue, especially while exercising

Two Is Better Than One: Combining High-Intensity Interval Training (HIIT) and Intermittent Fasting

Constant exercise plays a major role in intermittent fasting. Apart from consuming a nutritious diet, Mosley also incorporated high-intensity interval training (HIIT) exercises into his workout after learning about it while working on a documentary for BBC.

There's a train of thought that eating pre-workout is helpful because it gives your body energy, but I believe exercising in a fasted state is better. As mentioned, intermittent fasting gets your body to use fat as fuel instead of glucose or sugar. Exercising while fasting intermittently effectively forces your body to shed fat because of the body's fat burning processes, which are activated by exercise and lack of food.

HIIT workouts in particular are a good option because of the following benefits:

  • Greater calorie burn and fat burn
  • Greater workout efficiency
  • Better heart health
  • Greater endurance

Setting the Pace

Starting with your intermittent fasting requires planning and paying close attention to your body. They say that slow and steady wins the race, so don't rush when you're starting out.

Intermittent fasting is not a one-size-fits-all solution, and there are many ways you could go about it. Personally, I fast every day, restricting all my meals to a specific time frame (such as an eight-, six-, or even four-hour window). It lets me see my progress more quickly. If it sounds daunting for you, however, you can try these other methods:

  • The 5:2 Method: conceptualized by Dr. Mosley himself, this requires eating normally for five times a week, and fasting for the remaining two days by eating one-fourth of your normal daily calorie intake instead
  • Alternate-Day Fasting: developed by Dr. Krista Varady, the premise is simple – you eat normally on one day, and fast on the next day by eating about 500 calories only

These intermittent fasting methods may be different at first glance, but with dedication (and paired with an HIIT routine), the results are nevertheless the same – a gain for your body. Dr. Michael Mosley's story proves that you can make great leaps in your health with simple switches to your lifestyle.

Lastly, while intermittent fasting is a practice that can benefit most people, I would advise you to postpone your plans of fasting or other methods of calorie restriction if you're hypoglycemic or diabetic, until your blood sugar or insulin levels are back to normal. Pregnant women and/or breastfeeding moms should also refrain from fasting.

If you want to learn more about Dr. Mosley’s journey and the wonders that intermittent fasting and high-intensity exercise can do for you, read this article entitled "This Doctor Changed His Life with Intermittent Fasting and High Intensity Exercise – You Can Too."