Loyboy gave a complete answer. To the OP, I’d ask you to think carefully about what exactly is tiring you when you drive. Some people subconsciously grip the steering wheel hard and that is causing their arms & hands to tire nnati or cramp. Some people get sleepy. Some people are anxious or tense. Some people have neck or back or leg pain. Concentrate on what you are experiencing & then consult Loyboy’s post for how to fix that. It’s not a race, it’s s drive. Be comfortable while doing it.