Most top athletes train at least twice a day. Some three times. And some elite athletes, such as the London 2012 triathlon-medal winning Brownlee brothers, do as many as four sessions a day. That is not realistic, nor desirable, for most people. We have jobs to hold down, kids to feed, social lives to lead. But after running my first London marathon recently and experiencing the usual post-race flood of emotions - feeling great and hellish and at a loss as to what to do next, sometimes all at the same time - I wanted a fresh challenge. So I gave myself one. Could I train more like the pros by introducing more double sessions into my training and - as a one-off - spend an entire day at the gym working out?
It might sound a little mad, but the question of how many times a day you can train is a common enough question on fitness forums. As Dr James Carter, Head of the Gatorade Sports Science Institute International, explains, there is no straightforward answer. It depends on a number of factors, including fitness levels, exercise intensity, sleep and good nutrition. But Carter believes it is possible and can often be beneficial, even for amateur athletes like me.
"A greater fitness level will certainly help you, with faster recovery a benefit of increased fitness," he says. "However, the intensity and duration of the first session will play an important role in determining whether a second, or even a third, session is plausible. If volume is the goal, then intensity should be sacrificed. If quality is the goal, and training intensity high, then subsequent sessions should be avoided in close proximity and the remainder of the day dedicated to recovery."
Carter stresses that good diet and recovery between sessions is important. "Sip fluids throughout the day, aim to start any session rehydrated and then aim to replace exercise-related fluid losses in the hours after exercise has finished," he says. "Eat balanced meals throughout the day - but if the session lasts longer than 60 minutes, you should consider a carbohydrate-containing product during exercise, while 20-25g of protein in the hour after exercise is another sensible habit. Finally, ensuring between seven and nine hours of uninterrupted sleep will also help general recovery."
So, advice duly noted, and a decent night's sleep had, I left the house bright and early at 6am and found my way to the airy space of Equinox, a bag full of workout clothes, ready for something completely new and totally and utterly not related to marathon training. The gym had helped to plan a whole day of classes for me, mixing up different types of workout. A whole day of exercise and no running! This would be new. So what did my day start with at 7.15am? A treadmill class. Oh, God.
This, though, was a first for me: I've never done a running class before, nor one that involved wearing a headset to receive instructions. I persuaded myself it was, essentially, a different sport. In fact, it was 45-minute hill interval session, interspersing "pyramids" of effort where we were instructed to increase the gradient, with some flat out sprints, and finishing off with a "relay" race. 8.2km in total. A fun workout, but not a huge effort in comparison to some of the marathon training sessions I was used to.
Then an hour's break, a fresh vegetable juice, before taking an RX class. Generally speaking, I am suspicious of workout classes based on acronyms. I still have no idea what RX stands for, but this class is a revelation. It's essentially self-torture for half an hour involving a little spiky massage ball, a yoga mat and your own body weight. There are knots in my shoulders which have been there since about 1995 which scream in protest before submitting, with a whimper. Or was that me?
Then it was straight into a class that combines elements of Pilates, ballet and more standard strength and conditioning routines. I may have the fitness of a marathoner, but I have the flexibility of, well, a marathoner. While lithe gym-goers wrapped their legs around their ears, I strained to get my knees within focusing distance. The routine at the bar almost had me thinking fondly of 22-mile training runs. Almost.
As Carter explains, multiple sessions in a single day should work different components of fitness, ideally different areas of the body and different energy systems. "For example, the morning session may be a resistance-type session involving the upper body. In the afternoon, the session planned may be a cardio-respiratory workout, primarily involving the lower limbs from a load-bearing perspective, ie running."
The gentle spirits who designed my timetable had allocated me a good long lunch break. It was sunny out, I was near Hyde Park in London. Should I go for a run? No, I ate salads instead. It's not quite time to contact Runaholics Anonymous again.
My next class wasn't really a class but a one-on-one session with one of Equinox's top trainers. Essentially it's an MOT. Everything is measured: body composition (weight, body fat, and the like) then a full range of functional movement and postural checks, using rulers and tapes. Fortunately no major problems or weaknesses are uncovered, though this would be a very thorough way to identify - and hence try to correct - any major imbalances.
Then another gap in my schedule before Pilates at 3pm. Should I go and have a coffee? No, I decided to do some intervals on the stationery bike. If you are going to do something, do it properly, until you can't stand up, as no one has ever motto-ed.
It is worth stressing - again - that you do have to be sensible. I came to do this having run 60-mile weeks training for a marathon and having double sessions during a day. As Carter explains: "As training volume increases with multiple sessions per day, an increased injury risk is one possibility, especially if recovery is sub-optimal. Of course, training risk will increase anyway with the increased amount of time spent exercising per week. Furthermore, over-reaching or over-training is another danger.
It's important - as with any exercise - to build up gradually, eat well and take some rest days. Furthermore, as Carter points out, too many sessions can result in mental staleness, "with the individual gradually losing the enjoyment that exercise brings. Here, variety, as well as those days off, will help keep physical activity fresh."
A one-on-one session on the reformer beds was my last class of the day. If you've never done Pilates on a reformer machine, let me conjure up the picture for you. Take the Machine from The Princess Bride. Add impossibly bendy instructor, and exceedingly non-bendy runner. Anyone got Miracle Max's phone number?
I finished my day by getting a sports massage - which helped placate many sore muscles - eating a healthy dinner and crashing to bed early and sleeping like the dead. I didn't feel too bad the next day but listened Carter's advice and took it easy. Would I exercise four or five times a day again? Not immediately, no. But I am incorporating more double sessions - a run and, say, weights and core work - into my day. And I feel better for it.
The Brownlee Brothers (left and right) during the Olympics. They sometimes train four times a day. Photograph: Getty Images