Sure I have for years. I think a training journal is essential. And I can't count the times I have referred back to old journals to look something up. I keep mine in 8 x 5 looseleaf binders. I label them by year. I have quiet a collection.
Yes this will be moved to health and fitness. And generally body weight exercises are what you are looking for. Think of a gymnast. They have a great amount of strenght without mass and definately do not lack speed.
Okay, it is a good bit of information but please in the future cite the source of any article in the original post. There could be copywrite issues here. Please don't just copy and paste. Give the source proper credit.