Minimize as much as possible the wastes associated with the "nature" event.
Examples:

•  Organise cleaning teams for before and after the race
• “Plogging Challenge”: to go jogging while collecting rubbish
• Recycling bins
• And above all: raising participants' awareness to continue and make these habits in day to day life!

• Encouraging the bartering and resale of used equipment and the recycling of used clothing and shoes 

Avoid packaging if possible, recycling bins at aid stations…