Regular mace or dog mace (small enough to carry on any run and concealable) is the best option. If a dog begins to charge, spray a warning shot immediately. The dog will likely smell it, even from far away. If it continues to charge, then restart your spray when it's 10 feet away and don't relent.
Call animal control immediately. Have their number saved on your phone. When the owner of the charging dog approaches you, they will likely wonder why you didn't let their dog continue their charge (this will occur 99 times out of 100, many dog owners are not rational people). Tell them politely that you're calling animal control for resolution.
Always call animal control. They are on your side. They have to deal with irrational dog owners all day long, seven days a week. You may prevent a future attack if you involve them every time.