In reply to Mike Nolan:
> I've always struggled quite a lot with my endurance, specifically on steeper trad routes when I'm hanging around placing gear, but also on indoor routes where I eventually can't hold on any longer, my forearm/grip strength just runs out - I seem to get pumped quite easily.
>
> I've read about loads of different methods to improve anaerobic and aerobic endurance, but I'd appreciate suggestions from others, specifically things I can do on my own on bouldering and traversing walls. However, I'd still like to hear suggestions for things I can do with a partner.
>
Personally given that I have been climbing a long time I favour bouldering circuits for training endurance over routes as apart from not being dependent on a partner you have far more control over the intensity, number of moves and timing on bouldering circuits. These variables can be adjusted to train whatever type of endurance you seeking to train and given that you say you have read loads about anaerobic and aerobic endurance you will know what I mean.
There are a couple of practical points to bear in mind with circuits. Firstly if you get a partcular circuit dialled then you will start to move too fast on it. To slow yourself down count to three on each hold. Ideally get someone else to set the circuit so you dont end up setting something that already suits your strengths. Try to ensure the circuit has moves of similar difficulty without "stopper" moves.
With respect to routes 4x4's are usually pretty effective. This where you lead 4 routes in succession a level or two below where you would normally get pumped to form a set. Do 4 sets for a session usually alternating with partner who is doing the same thing. A short rope is handy as you can pull it through from the top quickly and so not have to untie between "reps".
Although old skool if you have any fingery local outside traversing walls (railway bridge walls, quarries) they are great way of getting stamina and its far nicer to be outside.