I am able to do chin-ups for about 3 reps. But when I try to do pull-ups, I can't lift myself up. Why is that? These are same exercises which works almost the same muscles. Does anyone have an explanation for this?
Also, when I do pushups, then after I am done, I feel like I have a loss of hearing for a short time. Is it normal or is this a breathing problem during exercise?
Technically speaking, that's two questions and you should split them apart, but they're also likely pretty easy to answer.
Chin-ups and Pull-ups use the same muscles, but at different intensities. Personally, I have similar results. I can do about six chin-ups, but only one or two pull-ups. Other people have had the opposite pattern. It depends on which muscles are more conditioned.
Temporary loss of hearing can have a few possible sources, but the most likely one is Eustachian Tube Dysfunction which can be exercise-induced. It's not that common, but it does happen. If it lasts more than a minute or so, though, see a doctor, as there are more serious conditions that this could foretell such as high blood pressure. Also, it's been linked to not breathing while exercising, so make sure you're not holding your breath while exercising.
