"How do I CrossFit regularly and not lose my specific fitness for an endurance event?" This is a question I've been asked probably no fewer than 100 times in the past few months. I believe it boils down, at least in part, to effective use of time trials in your training program. I and the long-distance athletes I train have been successfully implementing training programs that integrate CrossFit and sport-specific endurance work.
In each case, our times in our respective sports (running, rowing, cycling, swimming) have gotten faster. And our CrossFit times/numbers keep getting better too. A lot of people I've come in contact with in the last couple of months initially tell me that they think they have to choose to do either CrossFit or marathon/Ironman- specific training and cannot do both successfully. Well, I went on a 10-mile trail run a few weeks back on the same day I had a CrossFit Total lifting event. I ran well--not my fastest time on this course, but within 10 minutes. Then, within two hours, I set personal records on every lift (back squat, press, and deadlift) at the Total. This was a breakthrough day for me.
If you are training for a specific sport, you need to establish your goals for that sport. Are they attainable goals? Or are you like me and tend to set almost unattainable goals and then either hit or miss them, rather than set reachable ones that you can really commit to accomplishing?