Learning Sign Language is hard, expensive (mainly because it takes so long, the individual classes are moderately priced), but is not very physically taxing.
It is definitely social. If you use a group class, you have people to practice with. Even if you don't, the eventual idea is to talk to other people.
It's hard to know how many people know ASL, but it is the 3rd most requested translator language for the courts. Some people believe there are about 2 million Americans that sign using "American Sign Language" ASL, which would make it the 4th most popular language in America (English, Spanish, Chinese, then ASL). ASL was created by people that knew the french version (LSA) and the sign language used by many other countries is derived from ASL. So you might be able to make yourself understood by deaf French, Jamaicans, Nigerians, etc.
But more importantly, the people that speak ASL do not have as large a community. Most big cities have Spanish speaking neighborhoods and "China towns", but ASL users often have few people to talk to. Most Spanish and Chinese speakers also speak some English, but quite a few ASL can not hear at all. All of which means that if you do find someone that speaks ASL it's kind of like running into a fellow American while visiting a foreign country. You may suddenly make a new friend who has so much to talk to you about.
But it is a real commitment in time and money. You can't expect to pick it up in just a month. It takes a lot of practice as well. Worse, if you stop before you become good, you likely will end up forgetting everything you learn.
Sign Language classes are gender neutral, though my class was a bit more female than male. There are no age limits, the young and old can take them.
I took classes here: