Training on vacation

I just went through this same thing.  We were vacationing in Lake Tahoe so it was the perfect place to run and swim.  I just got up earlier than everyone and got out for my runs.  The days we were at the beach I played and lounged, but also brought my goggles, swim cap, etc. and did my swims as well.  It's doable, you just have to do it.  As for eating, I packed healthy options. It's kind of pain, but it was worth it.  I ate my usual breakfasts and lunches--but dinners out I was a bit looser--but nothing crazy.  I find that if I make 'deals' with myself on vacation I do much better.  For example--strict breakfast and lunch of the food I brought, and then enjoy a nice dinner.  I came back from vacation feeling good--I enjoyed everyday and didn't feel like I 'missed out' because I was so strict with my food pus I made the time to train.  The day after we got back I was right back to business.

Squeeze in an early morning run if you can a few times.  Running gear doesn't take up much space, so it's easy to pack it along on about any trip.  Same with swimming if you have access to a lake and are planning beach time at some point during the trip.

Meals, it's okay to live a little and enjoy some nice food on vacation, just try to avoid the junk calories in beverages and go with water as your meal drink whenever possible.  Cut a little here and there so that the calorie hit isn't quite so bad.

Expect to gain a couple pounds.  Hopefully not worse than that, but don't panic if it is.  When you get home, waste no time slipping back into the normal training routine.  If you haven't been running the whole time on vacatin, ease into it with some reduced mileage for the first week if you took more than a week off from the running.

Have fun!