Dan Gordon's squat challenge

Before we get back to unearthing the ancient history of human movement, it’s time to get the blood pumping here in the studio and at home with some movement of our own. Dan Gordon, exercise expert, got Katie Haylor inspired with an exercise challenge...

Dan - If we've got space, stand up. All I'm going to ask everybody to do is, I will be the timekeeper, for 30 seconds - just do squats. Hands on your hips or hands on your head, and just try and do them as fast as you possibly can. We just want to get the blood pumping a little bit.

Katie - Are you gonna do them with us Dan?

Dan - I'm gonna do them! Don't you worry.

Katie - Okay! Right. Is everyone ready?

Dan - We're ready. Here we go. Three, two, one. Let's go.

Katie - I'll practice my err...I don't know about my technique actually, nevermind!

Dan - Nice and steady, and trying to do nice relatively deep squats. Feel a little bit of burn in your legs as well as you're going down.

Katie - Dan my thighs feel like lead!

Dan - Oh okay! We're just over halfway, so we're going really nicely, Just keep that going, keep the old up and down movement going - really good. Keep it nice and firm in the stomach as well, so you're just holding that position. We're nearly there. And stop, there we go!

Katie - Okay. Right. Finding my chair again. I think I got about 11. Did anyone do better than 11?

Emma - I totally lost count. I don't think I'm able to do exercise and think at the same time it seems!

Katie - Maybe you just did so many that it wasn't worth counting after a while.

Emma - Yeah. Maybe I was just lightning fast. Yeah. You're absolutely right.

Katie - Eleanor, are you going to admit your score?

Eleanor - Well, I did some and then I decided that it was awfully hard work and so I got some biscuits out instead, so I apologise.

Katie - Ah wow, I was going to tell you off, but I just have to admire that. That's excellent. Jess, what about you?

Jess - Yeah. Yeah. I got to 18, but I was trying to get real deep as well.

Katie - Blimey! Wow. Well, I think I'm going to give you a little round of applause there because that's certainly a lot better than my 11. Dan, can I ask you about warming up - forum user Carl89 has recently weighed in on a discussion on our Naked Scientists forum asking actually what the point of warming up is. And he reckons it's due to increasing blood flow and enhancing flexibility of muscles. Is that right? And if we're talking about warming up, does the external temperature matter?

Dan - Yeah, this is a great question, but it's also one of those questions which opens up a can of worms. If we take, for example, doing cardiovascular exercise, then the whole notion of doing a warm up for that kind of exercise is to absolutely raise temperature.

But what we're trying to do is raise the temperature at which the cellular processes are operating, because all cellular processes work at an optimal temperature. So if we can get those processes increased, the temperature increases the rate at which those processes operate, it's sped up and becomes more efficient. It's also designed, those kinds of warmups, to reduce what we call an oxygen deficit. And whenever we start to exercise what you perhaps feel for the first few minutes, the exercise always feels very hard. You feel like you're struggling to breathe and so on. And that's because the cardiovascular system, the aerobic supply of energy, our kind of use of carbohydrates are all delayed. They don't hit their instantaneous, what we call, steady state. So you borrow energy from sources, which we refer to as being anaerobic. And really the consequence of that is what makes it feel hard to exercise.

So if you can warm up beforehand, what the warm-up does is it raises things like your heart rate, it raises your respiration rate. It raises the metabolic rate. So when you actually get into doing the exercise that you really want to do, there's less of a lag. And so you actually hit that steady state more effectively. The flip side to all of this is what about warming up for sports or exercises like strength training. Because in those sports, there are no benefits at all in doing anything which is cardiovascular based because the exercise that you're going to do doesn't stress the cardiovascular system. So in those kinds of exercises, what we suggest to do is what is called post activation potentiation - it's a very fancy term isn't it.

But, in essence, what it's about is preparing the neuromuscular system. And if we can prepare the neuromuscular system, what we can do is recruit more what we call motor units and the motor units are basically how many muscle fibres are recruited from a nerve. And the more muscle fibres I can recruit from a nerve, the more force and therefore the more load in the gym I can lift. We don't have to worry about temperature. We don't have to worry about heart rate and we don't have to worry about the flexibility issue. So it's very different. Depends on the sport that we're going to work with. You talked about the environmental temperature. If the external environment temperature is cold, like we're starting to get now, then the warmup doesn't need to be more intense, but what it needs to do is be sufficiently stressful. And what I mean by that is putting a strain on the biological system to raise the temperature enough, to ensure that we've hit that kind of required point for the exercise. So we will take longer to warm up in colder conditions.