If possible, just leave weighed-down branches alone. Source: Claire Tourigny, from the book Les 1500 trucs du jardinier paresseux
When snow or ice bends the branches of trees, shrubs and conifers, the best thing to do is … nothing at all!
Trying to clear snow or (especially) ice off a bent branch with a broom or shovel can do more damage than the weight of the snow/ice itself, as wood becomes brittle at temperatures below freezing. Even manually straightening the limb may cause the wood to crack.
When a thaw occurs, the branches almost always return to their original shape. And if some were to remain a bit bent, a temporary stake, added for a week or two in the spring, will usually be enough to get them back in shape.
Of course, if the weighed-down branch is blocking access to your walk or is otherwise in the way, you’ll have little choice but to try to raise it (but try a broom rather than a shovel). Otherwise, just let Ma Nature do her job!