What Is It?
Intermittent fasting (IF) has many different followings. Some people will fast for a few days a month, others will fast every other day (alternate day fasting or ADF), some will fast for 1 or 2 days a week and so on. I realized that none of these were for me simply because I enjoy eating and because I knew that not eating for a whole day would get in the way of social obligations. Then I came across a different approach advocated by a trainer by the name of Mark Berkhan that he referred to as the lean gains approach. He really likes to dig into the science behind intermittent fasting and has broken it down quite nicely. Truth be told I responded to it better than I thought I would.
The approach is simple and is a good middle ground for those who understand the health benefits of fasting (which we will address in detail in the future) as well as those looking to lose weight but maintain muscle mass. I utilize a 16/8 split in the day in which I fast and then eat. For 16 hours I eat nothing and then I have an 8 hour feeding window.
For instance my day looks like this:
530am - get up and go to the gym (3 days a week)
745am - off to work
12-1pm - I eat for the first time
3-5pm - will eat again if I am eating 3 meals this day
5-7pm - I have my final meal, which can end up ending around 8pm.
After 8pm I am done eating for the day. There are little tricks here and there but this is the gist of it. The most important thing to remember is that fasting and the benefits that come along with it are not an on/off switch. I usually have coffee in the morning because it is a mild appetite suppressant and because it has some effect on increasing metabolic rate. Beyond that it is pretty much water, more coffee or tea until lunch. People tend to confuse thirst with hunger and libations tend to reduce hunger until you eat. There are other hormones involved in this hunger process that will adjust to your new eating schedule in a few days such as ghrelin so you won't feel hungry.
What I have found is an ability to eat without fear of weight gain. Those attempting to lose weight will have a stricter diet than someone attempting to maintain a weight. For instance, if I am attempting to lose 20lbs as a 200lb 6ft male I am probably only going to be eating 1500-1800 calories a day. This will allow for weight loss at a timely rate along with additional exercise to assist in lean muscle gain. After that time when the weight goal has been reached a slight increase in calories would not tailspin the gains made and a more modest caloric consumption anywhere from 2000-2500 could be used to maintain weight. It depends on many factors but many of my clients have not had issues with feeling satiated or excessively hungry.
Why Should I Do It?
This is the most frequent question I receive. Many clients automatically believe what I say to be gospel but I encourage them to read the literature (or my site) on their own for the science behind it. After all, I couldn't say it if it wasn't true right? Sadly most of the misinformation in the world of weight loss and training is regurgitated by personal trainers and weight loss gurus who don't really have a grasp on the science and spew whatever they are told. This is true when you hear anything from "you're in starvation mode" to "eat 6 small meals a day or else your metabolism will drop."
Truth be told there are many health benefits to IF and this is just a small list:
- Increases insulin sensitivity which will assist in reduced hunger.
- Increases metabolic rate, another study.
- increased longevity
- reduced triglycerides and LDL
- increases cancer survival rates
- increases growth hormones
- increases neurological health
- increases autophagy (cellular recycling)
- increases metabolic processes
- improved protein synthesis
Anecdotally I have utilized this approach for some time and found stubborn body fat easier to eliminate with my clients without the hardships associated with a typical calorie restrictive diet. There are other tiny tricks to facilitate weight loss and increase lean muscle mass but the gist of the whole process is simple. Fast for 16 hours and then eat during the 8 hour eating window. Obviously focus on higher protein, lower carbohydrate meals as this will increase satiety and reduce unwanted calories. The easiest way to do this is to simply avoid grains and get your carbs from fruits and veggies as we have discussed before. Cycling macronutrients around days of exercise is another way to favor upregulation of fat loss hormones and we will discuss that in the future.
Hope this helped everyone with basic questions. I will continue to dig deeper into the whys and hows and feel free to send your questions as I know this was very basic but was simply meant to be an overview on what I have experienced and seen. Just remember to take your work out All The Way!