Coach... I did what you said in terms of adding weight to a backpack to get better at pull ups and it worked out amazingly. I've been trying to adopt the same principle with push ups but as I go up in weight I get concerned about the strain it is putting on my back seeing as though a dumb bell isnt exactly an even surface. Is this something that I should stop doing unless I'm using a weighted plate and just focus on reps alone? or is there some way to adopt your pull up gaining method to pushups?