I saw a good weight gaining diet here before and can't seem to find it again.
I am 6'1 170 pounds and have been stuck there for a couple of years. I need to seriously plan my diet out and get the extra calories in.
However, I'm an avid runner and cyclist and I don't want to eat things that are hard on my heart/cardiovascular system. Example...things that are high in salt...etc.
I want to gain weight and do it in a healthy fashion. I dont want to go to whataburger and get a triple meat and cheese...although its tempting. hehe.
Another thing that I think has helped me put on weight is Waxy Maize Starch from True Protein. At 260 I take in the following:
1.5 scoops Waxy Maize / 1 scoop Whey Protein
3 scoops Waxy Maize / 1.5 scoop Whey Protein
Also, you can gain the weight but it will be much harder with high levels of long distance running / cycling. I would cut that back some if you are serious about gaining weight. Perhaps replace a long distance run with some hills or sprint intervals. Also, SQUAT, BENCH, DEADLIFT, EAT, REST, REPEAT.
Healthy weight gain? No such thing. Eat your face off until you reach your weight goal. Any other method will only bring minimal to no gains and lots of frustration. Healthy weight gain is an oxymoron.