One of the most gratifying aspects of climbing is the feeling of accomplishing harder climbs. This means that you are getting stronger, and it feels good. Strength is built by low repetitions and high resistance. In a climbing setting, then, this means attempting difficult climbs in a measured manner with long rests between burns. After a good warm-up, try climbing a little, or even way, above your comfort level.
The goal is not usually to flash the route; redpointing is the more common objective. This refers to successfully climbing a route after previous attempts. Although redpointing generally refers to a style of lead climbing, the concept of working sections of a route and then linking them together also works well for top-roping or bouldering.
Difficult bouldering is also a great strength workout. A bouldering problem can be as short as a couple of moves, but success on those few moves can be both gratifying and beneficial in terms of strength gain. With each attempt at a move, not only is strength being used and built but much subtle technique is also incorporated that is memorized into movement patterns for the next attempt. Linking a couple of hard moves requires concentration, power, and good technique.
Work a hard route on a rope by “hangdogging.” Although once used as a derogatory label, hang dogging is a legitimate technique for building strength.
Climb till you fall, hang on the rope and rest, and try it again. Remember, the goal is not to hang on the rope, but to use the rope as a tool to allow you to build the strength and knowledge of a hard route so you can ultimately link all the moves together.
Climbers refer to the routes that they are working on as “projects.” Not everyone enjoys the project mentality; some climbers like to climb new things and do not like to fall. That is fine, too. But if you want to improve, you are probably going to fall.