Practice tonight will be indoors. Get a good warm-up and stretch (this should take 15 to 20 minutes), then move to the weight room for push-ups, hangs or pull-ups, and crunches.
Then move to the ergs -- do four 2000 meter pieces at a steady pace (control!)-- in other words, try to hit the same time for each of the four 2Ks.
We're back on the water on Saturday.