My long-term goal is to raise my onsight level from F7b (occasionally 7b+) to 7c as it's the style I find most thrilling. I think my weak points are maximum power and short power endurance, especially to be able to do less than perfect sequences.
The problem is, when I concentrate on bouldering and power for a while, I really lose my endurance, I get to the point where I can flash Fb6c boulders but get pumped out on a F6c route, which is really frustrating. I've tried doing one endurance session per week, but this means I can only do 3 power sessions, as I don’t recover enough otherwise.
Job-wise I can get away for 1 week climbing trips every 6 weeks, so I would like to stay reasonably fit to be able build up on-sighting experience (which I can't get at the weekends closer to home).
The question is how is it possible to combine strength gains without totally sacrificing endurance? Is it efficient to combine the two in one training session?
Reading between the lines, it seems like your weaknesses are pure power and pure endurance; you are operating somewhere in the middle.
You need to analyse your climbing and work out why you are falling off routes. Saying that you ‘focus on power for a while’ then you get pumped out on f6c routes, would indicate that your endurance levels and ability to recover are low.
It is definitely not efficient or a good idea to train both areas in one session; the more you specialise and focus in a session the more you will reap the benefits.
When you plan your training, always train power first when you are fresh, never boulder at the end of a session- very counter productive. Training power efficiently is a fine art and is a delicate balancing act between not doing enough and over doing it. Try to end your power sessions not completely wasted and give yourself a couple of days to recover. Unless you are just a boulderer, doing 3 or more sessions a week is too much. Your endurance will definitely suffer if you are doing this much.
It sounds like you need to train shorter problems, so you can climb ultimately harder moves. On 7c’s and harder you are starting to get into needing to be able to onsight English 6c moves, which are obviously hard. If you aren’t strong enough for this then it’ll never happen.
Weights can help if you have a weak area. For me I know my biceps let me down so I will focus on them. It is possible to do a weights session, have a few hours rest then have a short power boulder session. This is not something you can do for weeks but if you are short of time, it is a good way to fit things in. It’s very important to rest properly if you are training like this. It’s feels like you don’t want to but it WILL work.
Unless you are overly strong for the routes you are wanting to on sight (very unlikely), you will need endurance to be able to recover on rubbish rests. You will not be able to just climb without stopping (power endurance) as you will just get powered out very quickly and fall off without feeling very pumped but just not being able to keep going.
You need to work your recovery and your ability to find rests and use them.
On sighting lots of different routes just below your top level is good as you will be able to do the route but you will need to shake out in places but you shouldn’t find the moves too hard. You can then practice them and identify resting places on the routes (2-4) and make you stop at them for a period of 20-40 seconds and try to recover. This may feel hard at first if you aren’t used to stopping much on routes but if you practice this your endurance and recovery abilities will improve and your confidence in being able to recover will be boosted.
Once you feel this working start finding worse rests on different (harder) routes and seeing if you can do anything with them as this is what you might have to do before the crux on a route.
Basically, topping up your ultimate power levels will make moves feel easier and your power endurance will naturally be boosted and if you can up your recovery abilities you will be able to take advantage of poor rests.
Have fun trying it out over there in Luxemburg.