summer training cross country?

this summer i really want to get in shape and become a better runner. i currently run a 6:10mile in track and in the fall i am doing cross country. i am also playing field hockey. we have field hockey conditioning for 4hrs every day where we do running/agility stuff for one hour, play indoor hockey, weight train, and do a video workout. i want to do xc too but conditioning is the same time should i run by myself in the evenings?? i am afraid of overtraining and actually hurting my times. i cant really run outside during the day from 12-5 because it is super hot and sunny. i was also gonna do yoga and swimming for cross training. any suggestions on how to improve my xc times w/o overtraining? thanks!

CrossFit triathlon Workout

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CrossFit Rugby drill

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Looking for a summer sport for cross training for ski racing?

Need something inexpensive and that can help me with my agility, balance, explosive quickness and has a fear factor. Something that can test my limits and help me strengthen my muscles apart from my gym regiment. Up for almost any sport, live near a city so can find the appropriate place to go for it. Don’t particularly like water and can’t ride a bike very well.