If she fails to do so, she gets an H , and so forth. Climb hard in a gym for an hour or two and your hands and forearms are blitzed, your legs are sore, and your upper body longs for the nearest masseuse. Not only are you working your upper and lower body, you're developing balance, agility, flexibility, and concentration. But indoor climbing has taken on a life of its own. People who start out climbing a lot indoors often improve their technique quicker than their counterparts who learn outdoors.
Indoor gyms offer more consistent, sustained climbing.
You tend to get more bang for your buck when you climb indoors. Part of this is simple physics. Unlike real rock in the great outdoors, the spacing of the handholds and footholds in indoor gyms is set up with Homo sapiens in mind. That's where a good instructor comes in. Instead of bombarding you with a lot of information about positioning your body, an instructor will give you a few basic ideas and tell you to go play.