Intermittent Fasting, What It's All About
Free Health and Wellbeing Blog Intermittent Fasting, Weight Management
Well intermittent fasting is thought to be an effective way to lose body fat without losing muscle mass or in other cases increase lean muscle mass with minimal weight gain. This makes the trend not only appealing to the average joe trying to lose a few kilos but also to people in the sporting community, where athletes are trying to hit target weights for competition without losing muscle mass (Tinsley, Gann & La Bounty, 2015).
What Does It Involve?
Intermittent fasting is a form of calorie restriction, there are numerous ways this is achieved, but we will just talk about the main three here today.
1) Time Restricted Feeding 16:8
Is the most common method used, it requires a person to restrict their intake during designated hours and maintain a consistent eating pattern outside these hours. A common diet is the 16:8 which involved fasting for 16 hours consecutively followed by 8 hours of ad libitum food consumption. So a good way to look at this is to eat regularly between the hours of 9am – 5pm and nothing before or after. This is a common method used as many people are easily able to incorporate this into their daily routines (Levy & Chu, 2019).
2) Alternate Day Fasting
This method restricts calories by alternating feeding days with fasting days. Fasting days usually consist of 1 meal providing roughly 25% of the daily calorie requirements.
3) Whole Day Fasting
Whole day fasting is 1 or 2 days of complete or modified fasting (eating 1 meal a day) each week and regular eating the rest of the week (Tinsley, Gann & La Bounty, 2015)
There are definitely positive results for fast weight loss and it has also shown to help reduce blood pressure and improve metabolic disease risk markers (Levy & Chu, 2019). The underlying concept of intermittent fasting is during the fasting period, insulin levels drop, initiating the release of stored glucose, resulting in fat loss. Short term studies have found intermittent fasting to help improve insulin sensitivity (Aird, Davies, & Carson, 2018). When exercise is performed during a fasting period, it promotes the utilization of fatty acids and intramuscular triglycerides in the skeletal muscle as the primary source of fuel, this is what stimulates and promotes weight loss. However if training occurs directly before a fasting period or on whole day fasts, it will impair your ability to recover, this is due to the lack of muscle protein synthesis which is important for muscle repair and growth (Burke, 2010).
What To Be Careful Of
Intermittent fasting can be a great way to help reduce calorie intake and boost the metabolism, however it can also cause a lack of concentration due to low blood and brain glucose which can impair decision making (Appleton & Baker, 2015). Another thing to be wary of especially for those who are vegetarian or vegan, is nutrient deficiency, particularly iron and calcium. Finally, for those who do wish to follow this style of diet, it is so important to make sure during the eating times, that you are still eating a well-balanced meal and not eating junk thinking that the fasting time will make up for it. Your body still needs all its nutrients and forms of energy to keep you functioning, deprive your body of these things and not only will you not see the results you are hoping for, but there is also the risk of causing some real damage.
- Alyssa Michel -
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