Dropping weight, or more specifically, body fat, is a very common topic of discussion among most exercise and sports enthusiasts. How to prevent or minimise muscle losses is a big part of that discussion. Pure Edge’s consulting Sports Dietitian, Rebecca Hay of The Athletes Kitchen, takes us through an interesting study into this question.
Our level of muscle mass is major influencer of our metabolic rate – and loosing muscle will decrease this. The impact of decreasing our metabolic rate has long term effects on the success of our efforts to stay lean by decreasing the amount of energy we need to function. For those participating in exercise and sport, the loss of muscle may also lead to a decrease in performance.
There have been many, many studies done on this topic and there are also thousands, upon thousands of testimonials from companies and people telling us that they have the magic potion that will make this happen. Sadly there is no magic potion or diet or activity that leads to this.
So what do we do? What do we manipulate in our diets to either maintain or increase muscle mass and decrease body fat? And how much protein do we actually need?
A study published in the American Journal of Clinical Nutrition in January this year looked at how to manipulate lean body mass on a low energy intake with varying levels of protein intake. This was done in young men (sorry ladies and older men) over a 4 week period. They were randomly assigned to two groups:
CON – Control group receiving a diet that provided 1.2g protein per kg of body weight (above current recommendations for most individuals – however most of us consume more protein than this in our daily diets already), OR
PRO – Intervention group receiving a diet that provided 2.4g protein per kg of body weight.
- Both groups has their total energy intake restricted to ~33cal (138kJ) per kg of lean body mass (LBM). This is very low and provided about 60% of their daily requirements for maintenance.
- All foods and drinks were provided, including a predominantly whey protein and carbohydrate supplement, that was consumed immediately after training.
- The fat intake of the control group was higher than the intervention group (almost double) and the carbohydrate intake was matched in grams per kg of bodyweight.
- Both groups exercised 6 days a week in the gym and were also instructed to complete no less than 10,000 steps each day.
So what happened after 4 weeks?
- Weight loss was not significantly different between groups
- the PRO group had an increase in lean body mass (muscle) compared to the CON group.
- The PRO group had a greater reduction in fat mass.
- PRO and CON had similar gains in exercise performance.more gains may be made for the “leaner” group in their next phase of training. More gains may be made for the “leaner” group in their next phase of training but that was not part of this study.
What does this all mean?
In this group of young men a greater muscle gains and fat losses were seen with a low calorie, high protein diet than in a lower calorie diet with the a lower protein diet.
I listened to one of the authors of the study talk about the impact that such a low energy intake had on the participants – he said that most of them reported they though about food all the time and after each meal they would think about what they were having for their next meal. Most of them answered “hungry” when asked how they were feeling!
So the moral here is that this works. The higher intake of protein with an overall restriction of energy from all macronutrient groups works. A word of caution though – this level of energy restriction did leave participants feeling consistently hungry…..not the best way to feel if you are trying to do more than just train, sleep and eat.
Ref: Longland, TM., et al. Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial . Am J Clin Nutr. Jan 27 2016
You can increase your protein intake with the Pure Native WPI or Organic Pea & Rice Protein supplements from the Pure Edge range. Each serve will add an extra 22-23g protein. It is ideal to use these in recovery with extra carbohydrates – Pure Edge’s Re-Load Energy can supplement your carbohydrate intake.