The role of the gut and the microbiome
High performing endurance athletes are usually lean. Reducing excess body fat increases power to weight ratio, meaning it takes less energy to pedal or run – effects only magnify as distance increases or hills come into play. The feeling is that the lighter you are, the faster you’ll go. The effort to get to race weight, or reduce body weight and fat mass, seems to be a constant struggle for many endurance athletes.
But, while leanness can be associated with increased performance, it is not true that lighter always equates to faster. Drastically or quickly reducing body will most definitely not help performance and may, in fact, be damaging to health and/or performance.
So much of what we read, see and hear on nutrition and health has a bent towards weight loss and, typically, promotes the idea that it should be a simple equation: calories in, calories out. Unfortunately, though, that’s not true. foods means that we have to expend less energy breaking down and digesting that food. Even simple processing like chopping or mincing – a whole steak vs. a minced steak – takes mechanical energy to break down and yet calorie for calorie they may be equal. Similarly, cooking, fermenting and other methods of preparing or processing foods change the caloric impact of a food, making calorie counting a very confusing and inaccurate exercise. Energy required for digestion also differs by macronutrient – the energy it takes us to break down and digest protein is greater than that for fat or carbohydrate. Protein may suppress feelings of hunger for longer than carbohydrates with fat also having a satiating effect. That fibre in those carrots (and other whole, real foods) feeds the bacteria in your gut and is critically important in the weight loss/maintenance/gain game too. Not only does fibre make us feel fuller for longer, but fermentable fibres help promote a healthy gut microbiome, which is important in many aspects of health, including weight. Researchers have shown that different strains of bacteria glean different amounts of energy from the same foods, meaning some people get more bang for their buck than others even if they have eaten the exact same foods. In general, obese individuals have differing types of bacteria that obtain greater amounts of energy from the same foods than do lean people.