I often suffer from sciatica and that sounds like what you experienced. One of the worse things that men do to cause sciatica is to sit on our wallets all day. If this is you then try putting your wallet in your front pocket while you drive or fly just make sure the condom ring is at the back
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Someone else mentioned bending your knees when you reach down for something. This is good advice but also remember not to bend in a twisting motion as that can lock things up as well, make sure the item that you want to pick up is directly in front of you and use the strongest muscles on you body to lift, your legs.
Cheers.