What would happen to humans if we set foot on Kepler-442b, where the surface gravity is predicted to be about 30% percent stronger than that of earth?
If humans colonized the planet, would it then begin to alter our descendants' bodies significantly over time?
We don't have test results for exceeding gravity by little, for exceedingly long periods. Longest tests were of order of a week (see this substantial answer with links and data), at 1.5g acceleration (which, for all practical purposes simulates increased gravity) - that means a typical expedition, like the Lunar expeditions could operate in these conditions just fine, but a colony could encounter unforeseen health problems.
There may be techniques that could mitigate some of the problems of prolonged exposure - e.g. remaining immersed in water causes external pressure to mitigate a large part of the stress on cardiovascular system. Although high-G worlds are definitely low-priority when planning a manned landing; tyranny of the Rocket Equation makes launch/return from these exceptionally expensive.
