There is a pizza restaurant 300 metres down the road from my house. Does it take more energy for me to skip to it or run to it?
Simon Dales
Oxford, UK
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Running is much more efficient than skipping, which is why top athletes run. We could skip our way around the track, but the runners would beat us. Have a go.
Our ancestors evolved to be efficient at moving long distances. The best way to use as little energy as possible over a long distance is to walk. But running only costs a bit more energy.
Each gait has its own speed range. Walking is only efficient up to about 5 kilometres per hour (for an adult). If you try to go quicker – like keeping up with a friend on a bike – you will spontaneously start to run. Running gets more efficient the faster you go.
Pat French
Longdon-upon-Tern, Shropshire, UK
Different people run in different ways. Athletes are trained to run in a fluid way. This means their momentum – the way they move forward – is nearly continuous. A good runner seems to flow through the air as their weight carries them forward. Less experienced joggers tend to slow down before each push. This uses more energy.
When someone is skipping, they almost entirely stop going forward at each step and so lose momentum. They have to push their whole weight up and forward with each pace. It uses a third more energy to skip than even an amateur runner uses. (And even more on the way home carrying your pizza.)
Ron Dippold
San Diego, California, US
The fancy phrase for how much energy various activities require is the metabolic equivalent of task. A of 1.0 is what your body burns when you are lying or sitting still – about 70 kilocalories per hour for someone weighing 68 kilograms. A slow stroll is 2.0, so twice that. Running at 10 km/hr is 9.8 MET.
You can search for tables of METs for various activities, which can be fun – badminton has a MET of 4.5! Note that these tables don’t always exactly agree with each other, but you can compare numbers at least.
Many of the tables include skipping rope (MET 8.0 to 12.0), but all those I came across ignored skipping down the street. Luckily, a of 20 healthy young adults found that skipping on a treadmill burned 30 per cent more energy than running. That would give it a MET of about 13.0, which means you would burn more energy skipping to the pizza place – to fill up on more energy!
Conrad Jones
Llansteffan, Carmarthenshire, UK (500 metres downhill to a pizza restaurant)
I’m not sure which method uses more energy, but my advice for the young question writer, Jessica, is to keep skipping and running for as long as she can. With any luck, she will still be doing them in her 70s, unlike most of us boring adults.
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