you can,
Vigil used to have his runners do mile repeats at a park once a week, nearly every week of the year...according to the book "Running Tough"
The thing is you should have some weeks set aside for recovery...ie after a long season you need 2-3 weeks of easy running.
Then during a "base phase" the idea is to get yourself in shape by developing aerobic enzymes....enzymes that are destroyed when significant amounts of lactic acid build-up..
So, yes, you can and should do race pace work year around (I think)....but you can't be doing gutsy, full-on V02max repeats year around or you you will destroy those enzymes.
doing a lot of 400 repeats a goal 3k-5k pace with enough recovery (ie 1:30) should be fine. Doing repeat 1000s or miles at 8k-10k race pace should be fine. Doing strides of 150m at mile race pace is fine.
During a "base phase" you want to work on your lactate threshold more- because that is what is going to develop you aerobically to be a better runner in the long run. Rush in with V02max work before the LT work and you end up "peaking" too early and the "peak" doesn't last as long.
You just can't be going red-line in workouts every week of the year...just like you can't be in peak racing shape every week of the year. So do race-pace stuff, just don't cross LT effort early on while you are forming those all-important aerobic adaptations.
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