In all the years I’ve been advising athletes on sports nutrition, one pattern has persisted: athletes underestimate their daily energy needs – often massively. Read here whiy this keeps happening what the consequences are in a series of blog posts.
The body as an engine: energy & performance
If we compare our body with an engine, we score a pretty low efficiency – the ratio of how much energy (in our case calories consumed) we utilize to perform a certain mechanical work. While a modern gasoline engine achieves 35 – 40%, a good diesel engine up to 50%, we slack around 25%. That has its good reasons, but if ¾ of the energy more or less disspiate, it is still performance-limiting.
The sobering comparison with kitchen appliances
I remember an anecdote from 2003. At that time I was one of the first triathletes in Switzerland who controlled the bike training by means of power-measuring crank. One day I discovered that our 30-franc handheld mixer was able to put out more watts than I could at the absolute limit, I was a bit disillusioned. Today, thanks to Robert Förstermann, I know that this is also the case for other bad boys:
Give us our today our daily energy – but how much?
Our total energy expenditure (TEE) consists in the basal metabolic rate (BMR) and physical activity. The former covers our life support – that is what we need for breathing, having a functioning blood circulation and maintaining our body (tissue, muscles, blood, skeleton, etc.). The physical activity, obviously is the energy we burn while moving.
If this energy balance is positive (more energy comes in than is burned), we will gain body mass over a certain period of time; conversely, a negative energy balance will result in a reduction in body weight in the medium to long term. For the moment, I will leave it at this superficial consideration, because important details will follow later.
In part 2: The ambition for fast gains – why high performers often eat too little…!
