Over the past few days I have swum, run and cycled a few more miles with no major problems thank goodness. A couple of sessions have had to be dropped due to other commitments but I have managed to fit in all the key sessions. For beginners that is a trick to be remembered, you can miss the odd session but you must complete all the key weekly sessions. For marathon training and any other endurance event training for that matter, the key sessions are the long steady distance sessions (LSD). You can forgo the odd speed or interval session without any major detriment but start to drop the LSD sessions and you are asking for problems. These sessions are the building blocks of endurance events and prepare your body for the arduous event you are undertaking.
I would suggest that it is almost inevitable that your training will not follow the schedule from start to finish without some disruption, so don’t panic if you have to miss the odd session. Even the professionals have disruptions in their lives. The important lesson to learn here is that how much you miss is, to quite a large degree, within your control.
There is nothing easier than convincing yourself that you just can’t do a session whereas it is much harder to work out how you can fit it in. Look at the options of an early rise to get the session in before work, moving meetings to allow you to take an extended lunch or even, as some of my training colleagues do, take every Wednesday as holiday at the point in their training schedule that requires 6 to 7 hours of training in one session. This may seem crazy to you but the driving force here is the commitment to give it your best shot and hopefully reap the benefits at the race.