Another common route to injury is having inappropriate footwear. That old pair of cheap trainers you've worn for years may feel comfortable but is just not suitable for marathon training. Most people have some level of muscular imbalance, which goes unnoticed in everyday life but is brutally exposed when you start running tens of miles per week. So, before that happens take yourself to one of the many local specialist running shops and have a video gait analysis before buying anything. Modern running shoes come in a variety of styles to suit individual gait, so don't be tempted by first pair that catches your eye. Unless you already know your pronation style you need specialist help. Beware also of cheap internet deals. Yes, you can find some good bargains, but repeating what I've said already, unless you know what type of shoe you need then saving a few pounds by buying online could prove to be a costly mistake and could cost you your marathon place.

The goal of any training programme is progression, which just means doing a bit more each week so that your body becomes accustomed to the extra demands you are placing on it. Don't be tempted to overdo it by increasing your weekly or long run mileage too quickly (10% per week is a good rule of thumb), failure to adhere to this rule is the most common route to a running injury. On the other hand if you don't stretch yourself a little each week you won't progress, so it's important to find the right balance. Varying your weekly runs is a good idea and helps to avoid boredom. Besides a weekly long run add a shorter faster run and two or three easy runs of varying distances. How long is long and how short is short will depend on your current fitness level and running experience and will change as you progress.

With 13 weeks to go to London you should now be well into your stride. If you're lucky enough to have a London Marathon place and haven't started training yet then don't delay a moment longer. For those just seeking to complete the marathon without any particular target, by the end of January you should be aiming to jog or run/walk 10 miles or to train for two hours and should be training at least three and ideally four times per week.

For those chasing a particular finish time then you should calculate what that means in terms of your required average marathon pace (eg, to finish inside four hours you need to run at 9 mins/mile) and should structure your weekly runs so that some are faster, your long run is slower and at least some sections of your other runs are at marathon pace. You should try to train five time a week taking your rest days after your most intensive sessions.