Runner's World has a great article (September issue not yet online) about how experts are challenging conventional thinking.
1. Is it necessary to run up to 60 miles (80 km) a week, to prepare for a marathon of 26 miles (42 km)? One successful program takes runners up to no more than 40 miles, with a very long run/walk peaking at 26 to 29 miles. The key is to add runs that are short but intense, as well as at least two days of cross training. There is "little correlation between weekly mileage and marathon performance, especially for novices--but a high correlation between high mileage and injury frequency."
2. A similar point: speed workouts can be fewer and less intense than many runners think.
3. Some say train the same year-round, rather than do far more miles close to a race than during a recovery time.
4. Cross-training is more beneficial than some think (this can mean a good workout with little risk of classic runner's injuries).
5. Strength training may not be particularly beneficial.
6. My favourite: stretching may not help with running, and there are lots of cases of runners injuring themselves while stretching. Since the magazine includes instructions on working the hips, I take this to mean: stretching the running muscles, which are already getting a workout, may be a waste of time, but strenghtening the core muscles and hips, which help with running and avoiding injuries, is always a good use of time.
7. Massage may do more harm than good.
8. Consuming carbs before a long run may be counter-productive: for a marathon, you need to prepare for running in carb deficit, since that will happen no matter what you do.
UPDATE August 2:
9. Fluid intake: it may be better to be guided by thirst, even when exercising, than to go beyond this and risk over-hydration.
10. Correct shoes. This interests me because I developed a bit of foot trouble before the Acura 10-mile on July 19: is it better to go "up" to the amount of both support and cushioning in a running shoe that feels comfortable, or to deliberately scale back on the structure in a shoe and "feel the road"? "[Shoes] prevent the nerve endings on your feet from sensing the gravitational stresses of each footstrike and making small adjustments with each stride to disperse the stres. Research has shown that so-called protective features actually increase injury frequentcy."