Clothing

Again, if you know what is most comfortable for you the conditions you will encounter, go for it. Generally, aim for lightweight flexibility. My own outfit consisted of split running shorts, a polyester t-shirt, a lightweight beanie, mid-weight wool gloves, lightweight arm warmers, and a windshirt and windpants. This system worked well: I was comfortable from start to finish, and I was able to make quick thermoregulatory adjustments using the gloves, beanie, and arm warmers. The one change I may make for next time is to leave the windpants in the car—it was 29 degrees when I started but within 20 minutes it was warm enough for shorts.

Pack

You have two options: a waist/bottle pack or a backpack. I prefer a backpack: they feel more natural (to me, at least), they carry weight better, they do not restrict hip movement, and they do not cause running shorts to ride up. The features of an ideal pack for this endeavor are: 500-750 cubic inches of volume, hip belt pockets, exterior pockets, and a chassis that minimizes bouncing (i.e. a good waist belt, a sternum strap, and load compression straps).

Water containers

You have four options: squeeze bottles, a reservoir with hose, collapsible bottles, or a mix of the above. Squeeze bottles are easy to fill and drink from (you can store them in side pockets, lash them to your shoulder straps, or use a hand pouch), but their carrying capacity is limited. They are ideal when water sources are frequent and/or when minimal water is needed. Reservoirs with hoses are easy to drink from, they carry well, and they offer big volume capacities; but they are difficult to fill, and estimating the remaining fluid volume takes familiarity. They are ideal when water sources are far and few between and/or when you are consuming lots of water. Collapsible bottles offer superior volume-to-weight ratios and high volume capacities, but they are difficult to drink from when on-the-move and they are not as easy to fill as squeeze bottles. They are ideal for hiking.

Lighting

If you expect to be traveling in the dark, you’ll want a bright, lightweight LED light. I prefer the Petzl Tikka XP, which I have re-threaded with a 40″ x 1″ webbing belt so that I can wear it around my waist—this results in greatly improved depth perception of on-trail obstacles like rocks and roots. Even if you do not plan to travel in the dark, it may be prudent to carry a 1-LED light, like the Photon Freedom Micro. In the event that your plan goes awry (e.g. if you bonk, get lost, or are slower than you think) you will not need to spend the night in the Canyon without adequate overnight gear.

Trekking poles

If you plan to run most of the trip, they are probably not worthwhile—they are awkward to carry while running, and they add 12-16 ounces to your load. But if you plan to hike all or most of the miles, plan to use a pair—they will save your legs.