If you are in an extreme heat area:
: If you are feeling dizzy, disoriented, clammy, affected vision, throbbing headache, vomiting, or your skin is hot/dry. Be aware of heat exhaustion and stroke signs (http://www.cdc.gov/niosh/topics/heatstress/)
. Ride with a buddy in high heat areas and carry a cell phone. Advise someone of your route and an expected time of return. If you have not returned, have them come search for you!
2) Increase your water intake to 32 oz per hour of cycling in high heat area! You could drink half water and half Gatorade or half saline solution (1-3 packets of salt to a quart of water). High heat areas will cause you to lose salt! It needs to be put back in. Drink every 15 minutes whether you want to or not.
3) Cycle in the cooler parts of the day. You may have to cycle as late as 8:30 PM or as early as 5:30 AM in order to achieve this. Cycle at a slower pace to exert less. You will get exercise without inducing dangerous conditions.
This challenge is meant to be safe. If conditions in your area make cycling unsafe for the day, skip the day.