Should I redefine or reassign a variable in a loop?

Supposing I need to iterate over something and set a variable in every cycle, like this:

for (int i=0; i < list.size(); i++) {
    final Object cur = list.get(i);
}

this redefines the variable everytime, so I’m concerned that that might pollute the memory.

The alternate option is to define the variable once and then reassign it every iteration, like this:

Object cur
for (int i=0; i < list.size(); i++) {
    cur = list.get(i);
}

would this be better in terms of memory? Would it make any difference? What if cur is a primitive type instead of an Object?

Don’t tell me to use foreach, I need the counter, this is just a simplified example