For those of us who have never trained, I have a suggestion.
Put on some gloves and attack a heavy bag. Preferably one of those soft kickbox fitness bags that won't hurt your hands. Attack for 1 five minute round. when you can't throw anymore punches or kicks just grab the bag and rassle it around.
I guarantee the bag wins. If you last the full 5 minutes, you done good.
Now, multiply the intensity of that workout by 10 and you have a good hard sparring round.
Multiply that sparring round by some factor and you get the intensity of a fight.
A 5 minute fight would kill some people.
Don’t pick a fight with an old man. If he is too old to fight, he’ll just kill you.