I’ve managed to put on weight, infact I’ve found cycling helped me increase my weight. I was a weight weenie, unhealthy 49 kilo’s (5’8″) now 63 kilos, that’s 30% weight increase, which took about a year. I found eating little n often helped me put the weight on, that and cycling gave me a big appetite, on average eating between 3000-4000 calories a day.
If you want to get toned, then I suggest the Insanity Workout, again you’ll be eating like a horse, I found I needed to remind myself to eat, otherwise I lost weight.
I found it was more about a lifestyle change, increased my cycling and sports, increased the frequency of eating (currently have breakfast possibly another at 10ish, lunch, another lunch at 3, tea at 6 then cereal around 10ish).
Tried Weight Gain, which works, until you stop using it! A good substitute is Milk, I drink lots!
Basically one thing is not going to change your weight, comibination of all these and you’ll be on your way. Also don’t weigh yourself all the time, I found as soon as I stopped caring about how much I’ve put on, the weight sorta flew on, until I hit my current weight.