Even the fittest athletes can get fitter. Personal Trainer Steve Mellor reveals how to workout like a pro and improve your VO2 max

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For most of us the ability to measure our fitness  levels can be easily monitored by a number of things; how long we can run before spluttering and stopping, the ability to complete not one but two burpees, or how quickly we recover from a gruelling HIIT workout .

So how do top athletes, with nowhere to go but up, measure their improvements? Quite simply, they work on their VO2 max.

Regarded as the holy grail of fitness by many within the workout world, VO2 max is one of the best indicators of a person's aerobic capabilities and is an important determinant of their endurance capacity during prolonged, submaximal exercise.

What is your VO2 max?

So, what does it mean? Well, as you increase your effort when you exercise, the amount of oxygen you consume to produce energy increases. However, there is a maximum level of oxygen consumption, beyond which any increases in exercise intensity don’t lead to further increases in oxygen consumption - and this is called the VO2 max.

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“Essentially it’s the maximum volume of oxygen that an athlete can use,” says Personal Trainer from  Freedom 2 Train ,  Steve Mellor . “It’s a product of many things, which range from your heart rate, the amount of blood pumped out of the heart in every beat, the amount of oxygen you inhale in every breath, the amount of oxygen that travels from your mouth into your lungs and from your lungs into the blood, the speed at which we can get that blood to the muscles, how much energy you use in each second of exercise, how much lactic acid is produced at a given intensity, how you utilise carbs and fats as energy and much much more.”

“It can be measured in different ways, but the most common is millimetres per kilogramme of body weight per minute,” Steve explains. Roughly, the higher the number, the more oxygen that gets to the muscles and the faster or longer you can run.

Studies have shown that the average untrained healthy male will have a VO2 max of approximately 35–40 mL/(kg·min). While the average untrained healthy female will score approximately between 27–31 mL/(kg·min). The highest ever recorded was that of Norwegian cross-country skier Bjorn Daehlie, who boasted a staggering VO2 of 94.

Contrary to what you might think however, a high score is not entirely indicative of a top echelon sportsman. “Oxygen is only important in sport when we are looking at over 20 seconds of effort,” says Steve. “So, for example, Usain Bolt is the fastest man on earth but his VO2 max will be pretty average. However, someone like Jessica Ennis who trains for events from 1s-2 minutes will have a far greater VO2 max.” If you are able to raise this threshold though, and therefore increase the amount of oxygen your body can utilise in a minute, the fitter you can become.

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How to increase your VO2 max

The extent by which a person's VO2 max can change is dependent on a number of factors. Firstly, it depends on the athlete's starting point. The fitter an individual is to begin with, the less potential there is for an increase, which is why many elite athletes hit this peak early in their career. There also seems to be a ‘genetic upper limit’, whereby further increases in either intensity or volume have no effect on aerobic power. Indeed studies suggest that heredity determines up to 50 per cent of people's endurance ability and that this upper limit is usually reached between eight to eighteen months of training.

Either way, there are a number of training techniques that can be adopted to help influence and improve your aerobic activities. Here are some top tips from Steve on how best to vamp up your VO2.

  • Get your heart rate up, and keep it up – work with intervals from 30 seconds to 10 minutes. They work on different things but all push your VO2 max higher.
  • Work out at an intensity where your body is working hard at around 8:10 - but you can still keep going – this is a tempo run for runners and should last between 20-40 mins.
  • Get stronger – exercise is always about moving a relative load, whether that’s your own weight or the weight of a bike etc. The stronger you are, the less stress this puts on the body and you can become more efficient.
  • Use a stochastic approach to exercise. Take the intensity up, then bring it down to a moderate level, then take it back up and repeat. This means your body accumulates lactic acid in the high intensity effort and then clears it out of your muscles in the moderate intensity.
  • Focus on the sport/exercise you want to get better at – it’s good to cross train but there are lots of physiological and biomechanical gains that only occur when you’re training specifically for the sport you’re looking to improve. Specificity is key.

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