I haven't been working out for four months due to injury. I am starting crew and wonder what exercises I should focus on.

I think that the main muscle groups involved are:

Quads and glutes
Lower back
Lats
Biceps

So I was thinking focusing on the leg press with then some horizontal rows then some romanian deadlifts. Obviously I will do chest press and shoulder press as well.

Do you think that focusing on these muscle groups is a good idea for increasing racing times. I am aware that I will have to work alot upon muscle endurance.

Any help would be appreciated

Someone who is more knowledgeable than I am can correct me if I'm wrong, but I'm not sure if pushing exercises (chest press, shoulder press) would really help with rowing. In general, they're good, but I'm not sure how they'd help with rowing. Those are mostly for triceps, pecs, and deltoids. I would think for rowing, you'd want to work on your traps and lats and biceps using curls, pull-ups, and rows. But the leg exercises sound good to me.

Thanks for the reply
I am aware that working the tris and pecs is unnecessary for rowing, I would just do those to get a full body workout.

My suggestion is to talk to the guys at the rowing club and see what they are doing and what they suggest for your particular discipline.

I want to get into sculling next year, so I've already spoken to a few of the rowers at the club here to get myself ready for the challenge. The club members were more than happy to provide me with lots of information.

The bottom line is they don't want people to fail or get a bad opinion of their sport. They will accommodate you if you're serious about doing it.

As someone who's competed at national championships in Australia (albeit as a lightweight) and who coaches U16-U23 rowing, I would recommend that, if you want to increase your boat speed and hence decrease race time (which I think is what you actually meant) do squat jumps. They are fantastic for building power, try and do them every day. When you're first starting out do at least 5x20 a day and build up.
Core stability is really important as well so make sure you work your abs and lower back.
A common mistake is to neglect the hamstrings, they need to be strong as well as the quads and gluts.
Shoulders need to be strong as well to provide the acceleration at the finish.

Most important things to remember though are:
a) Rowing is an endurance sport. It doesnt matter if you can row the first 500m in 1minute. If you can't last the race that means bugger all, especially in a crew boat. Don't neglect to build muscular endurance and, even more importantly, your aerobic capacity.

b) Rowing is a technique driven sport, finesse is just as important as grunt. Get in the boat and row. Row, row and then row some more. I cannot stress enough the importance of correct technique, timing and balance. Spending the time to row correctly (placement, posture, not washing out, balance and timing are the sacred five I hammer my crews about) will reward you more than just slogging it out with weights or on an ergo.

Hope this was of some assistance