Then that's your problem. First, they really shouldn't be, if they are integers you want an integer field, it is faster and more appropriate. Then this would work.
UPDATE main SET `ohs`=16, `ohst`=16 WHERE `name`='Bob'
because you you don't need to quote integer fields. What I find surprising though is that this should give you a mysql syntax error and it doesn't, and is instead inserting a 1. Try quoting your fields, which is required on textual and date types.
UPDATE main SET `ohs`='16', `ohst`='16' WHERE `name`='Bob'