I'm beginning training for my first marathon (chicago in oct). I have been running 7 miles 3 days a week (mwf) for over a year now. I've been cross training tue & thurs by attending a 45 min stationay bike class. I'm thinking of keeping my usual schedule and adding long runs on the weekand and possibly some interval training on tues & thurs in addion to my spin class. I want to be as prepared as possible, but I don't want to over/under train and thus cause injury. Does anyone see an issue with using this schedule until the race in october?

Thanks for any and all comments.

I just saw the "rules" section, so I'll add the following info to my post ...

Height 5'10"
Weight 170
I'm aiming to do the marathon in under 4 hours, my typical training pace is 8-9 mins/mile (temperature dependent).

Thanks again

First, I commend you on looking into this so far in advance to give your body a chance to adjust.

I'm assuming that you mean that you run 21 miles per week with three 7 milers and xt twice a week. This is a good start. For the months of February through May I would concentrate on building up your base mileage before you begin any marathon specific training. Rule of thumb is to add 10 percent per week, but it is safer to not up the mileage weekly, but say every other week to reduce injuries. So run say 23, 23, 25, 25 miles per week etc. In regards to the long run, I would push one of 7 milers off to the weekend and add a mile everyother week until you reach 12 miles. If you need more weekly miles, you could add a fourth day of running during the week and just run it as an easy recovery run. You will get more benefit from putting in the mileage than from interval workout at this point.

If you are looking to complete a 4 hour marathon, then 7-8 minute miles is too fast for training. A 4 hour marathon translates to about 9m 10s per mile. Your long runs, recovery runs, general conditioning runs should be a minute slower than this pace. This will feel really slow, but you do not want to tire your body to the point that you cannot complete all your workouts. Tempo runs should be run at marathon pace and lactate threshhold runs at what pace you can maintain for an hour (15k to 1/2 marathon) - but do not keep up for the full hour - maybe 30 to 40 minutes. Tempo runs are longer in distance then lactate threshhold runs. For instance, this sunday I have a long run of 16 miles, I'll be running 10 of the miles at marathon pace. Tuesday of this week I ran 9 miles with 5 miles at 1/2 marathon pace. Don't forget to encorporate reat and recovery days into your workouts to let your body recover.

Run a 10K race at the end of may. There are calculators on the web you can check to estimate your marathon time based on other distance races. Just be warned that you should add 10-20 minutes to the estimated marathon time as these as just that - estimates. You can then adjust your training paces based on that. Also include races at points during the traiing cycle to access fitness levels.