danimal is right about one thing- most people will say don’t do XC. In fact, Chances are Danimal will be the only one who will say do XC. That doesn’t necessarily mean he’s wrong, he just has a different approach then pretty much everyone else . If you want to focus more on track instead of football, then I’d recomend you do track workouts instead of running XC. You can find ideas for that all over the boards.
As to why XC will probably not be beneficial and may hurt is because it develops your slow twitch muscle fibers. Sprinting depends on fast twitch muscle fibers, and XC will force your fast twitch fibers to adapt to a slow twitch type of workload. While your fibers can’t convert or anything like that, they can function in a way thats more like slow twitch (distance running) then fast twitch (sprinting). You can develop the fibers back to a more fast-twitch behavior with training, but you’d be putting yourself through more work then you have to.
I might suggest doing extensive tempo interspersed with acceleration and maybe a little maxV work instead of XC.
If you want to focus on the 400, maybe try making those extensive tempo runs anywhere from 200-400 meters, with 300m being your standard distance (and then you can play around with distances and exertion %’s from there).
The benefits of doing extensive tempo over XC are that you’ll be working the energy systems that are more actively used in your events, you’ll be able to maintain good running form (XC tends to degrade form in a hurry), it’ll be easier for you mentally because its something you’re more accustomed to.
However, all that being said, if its a choice between XC and nothing, then go with XC. Anything is better then just sitting around.
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