Fat Ox Endurance Runs 
November 22-24, 2024
48 Hour | 24 Hour | 12 Hour | 6 Hour
100 Mile | 100K | 50 Mile | 50K
2024 USATF 24 Hour Championships
Goodyear, AZ

What started as an ‘ultra-experiment’ for young Nathan Coury’s college thesis on “fat oxidation” (fat-ox) and ultra running, becomes a 48 hour family fixed-time festival celebrating our season at Nardini Manor. Note we’ve moved venues to Estrella Mountain Regional Park


We beefed up the original Ox to bring you 6, 12, 24 or 48 hours of ultra fun. While previously held at Nardini Manor, this event will now be held on a 1 mile concrete loop at Estrella Mountain Regional Park.

Run your own experiment and push beyond your limits on the USATF Certified 0.988178 mile course.  It’s perfect for your first ultra, your first 100 mile, or your own personal best; a 48 hour time limit to discover your inner animal!

We are excited to announce that the 2024 Fat Ox Endurance Runs will again host the USATF 24-Hour Championship on November 23, 2024!

We’ll have a fully stocked aid station directly on course and you can setup trackside for ultimate convenience. we host a fully stocked aid station 24 hours a day. We will prepare breakfast, lunch, and dinner each day in addition to having many of the traditional staple items available at all our events. Staple items include peanut butter & jelly sandwiches, bean roll-ups, cookies, candies, coffee, soda and sports drinks.

Camping will be available for an additional fee on site.

Invite your family and friends to spectate, cheer and participate!

Volunteers Needed – Signup Now

Join us for a fixed time festival as a final lead in to Across The Years at the Fat Ox Endurance Runs!

Register NowMail In Entry Form

Location

Estrella Mountain Regional Park
14805 W. Vineyard Ave.
Goodyear, AZ 85338

  • Gender cut long sleeve shirt
  • Chip timed race results
  • USATF Certified Course
  • Well stocked aid station
  • Finisher Award (custom race buckle for 100 Mile, 200 Mile)

REGISTRATION

Entry Fees*
Until 6/30 Until 10/20 Until 11/18
48 Hour $260.00 $290.00 $320.00
24 Hour $190.00 $220.00 $250.00
12 Hour $140.00 $155.00 $170.00
6 Hour $100.00 $115.00 $130.00
100 Mile $220.00 $240.00 $260.00
100K $150.00 $170.00 $190.00
50 Mile $130.00 $145.00 $160.00
50K $115.00 $125.00 $135.00
*Prices DO NOT include City of Goodyear taxes

Entrant Limit

250 Runners

Registration Options

Online registration closes on 11/18  at 11:59 PM. If spots are available, registration will be available at packet pickup and on race day.

RACE DAY INFORMATION

Race Day Tracking

Your time and distance for each completed lap will be recorded automatically using a timing chip on the back of your bib. Please do not bend or fold your bib across the chip as this may alter your results. Up-to-date lap totals will be displayed on a TV screen, and will be broadcast to the race website as often as possible. Invite your friends to watch your progress online during your run.

Please make sure to wear your bib at all times as you run the track.  Note that laps will not be recovered by timing if a runner forgets their bib.

Course Records

48 Hour
Men: 256.937 Miles – Yiannis Kouros (’05) *
Women:  215.31 Miles – Fumie Sata (’03 @ ATY)

24 Hour
Men: 149.13 Miles – Yiannis Kouros (’05)*
Women: 130.49 Miles – Stephanie Ehret (’03 @ ATY)

12 Hour
Men: 80.54 Miles – Jake Jackson (’19 @ Jackrabbit Jubilee)
Women: 69.28 Miles – Kristina Pham (’17 @ Hotfoot Hamster)

*Nardini course records are calculated from several events throughout the years on the Nardini 500 meter loop. Yiannis Kouros set both 48 Hour and 24 Hour records on this course during ATY in his 2005 72 Hour Run. These records were  from his 24 and 48 hour split time.

Results
2023 | Results
2022 | Live Results
2021 | Results
2019 | Results

Site Map

Race Day Schedule

Please arrive early to park, check in and warm up prior to your run. Restroom facilities are located along the course just west of the start/finish area.

Timeline

Friday, November 22
6:30 AM – Estrella Park Opens for Setup
6:41 AM – Begin civil twilight
7:00 AM – Packet pickup/race day registration begin
7:07AM – Sunrise
8:00 AM – 48 Hour / 24 Hour / 12 Hour / 6 Hour Start
9:00 AM – 100 Mile Race Start (Starts 312 meters on course)
2:00 PM – 6 Hour Afternoon Start
5:24 PM – Sunset
5:51 PM – End Civil Twilight
8:00 PM – 12 Hour / 6 Hour Evening Start
Moon Phase: Waning Gibbous
Illumination: 56%

Saturday, November 23
6:42 AM – Begin civil twilight
7:08 AM – Sunrise
7:30 AM – Packet pickup/race day registration begin
8:00 AM – *USATF 24 Hour Championship / 12 Hour / 6 Hour Start
8:30 AM – 100K Race Start
9:00 AM – 50 Mile Race Start
9:30 AM – 50K Race Start
2:00 PM – 6 Hour Afternoon Start
5:24 PM – Sunset
5:50 PM – End Civil Twilight
8:00 PM – 12 Hour / 6 Hour Evening Start
Moon Phase: Last Quarter
Illumination: 46%

Sunday, November 24
6:42 AM – Begin civil twilight
7:09 AM – Sunrise
8:00 AM – All Races End
8:30 AM – Awards (Fixed Time Events; Fixed Distance Awards & Podiums will be celebrated at the conclusion of that specific race)
9:00 AM – Breakdown/Camp Checkout

Location

Estrella Mountain Regional Park is located in the Southwest area of the Phoenix Metro area set against the backdrop of the Estrella Mountain Range. The course will utilize the newly built 1 mile walking path around the grass turf area in the park surrounded by picnic Ramadas.

The Aid Station tent will be easily accessible right on the course. The timing tent will be just North of the Aid Station with timing mats that you must cross each loop. You can setup your own table, chairs and pop up next to the course for no charge. Camping will be an additional fee due to Maricopa County Park Regulations located approximately 400 feet from the course in an overflow dirt lot.

Awards

Top three male and female performances will be awarded in the 48 hr, 24hr, 12hr, 6hr, 100 Mile, 100K, 50 Mile, & 50K. *Fixed Distance awards/podiums will be celebrated at the conclusion of the fixed distance race.

Parking

There is a $7 per car per day entry fee payable upon arrival at the Maricopa County Parks entry gate. There is ample parking on site adjacent to the venue.

Drop Bags

We will have an area specified for your personal drop bag along the course that will allow for easy and quick access.

Volunteers

We can’t produce our events without our awesome volunteer team. We have a few positions available here. 

Course Marking / Lighting

The course will be easy to follow with cones and flagging to ensure you stay on the correct path. Unlike Nardini, there are not lights at this venue, so you will need to bring either a flashlight, headlamp or both to light your way around the course at night.

Camping

We are excited to offer several camping and tent rental options at Fat Ox. Maricopa County Regional Parks does have a nightly camping fee which we will post more details on soon. Camping will be available Friday & Saturday nights.

The camping area opens Friday, (Race Day) at 6:30 AM for camping setup. Campers have the option to set up their tents in a specified area approximately 400 feet from the race course. The park has moved our camping area slightly away from the course.

Tent and cot rentals will be available for your convenience. These will be located at a camping area approximately 400 feet from the course. You may reserve a tent and/or cot when you register.

All rentals will be setup when you arrive. You may check in to receive your tent anytime after 7:00 AM on Friday. Tents will reserved on a first come, first served basis.

Large Tent – $65 – These are 8 feet by 12 feet and are large enough to stand up in (for most people) and may also fit two cot rentals.

Large Tent + 1 Cot – $85

Large Tent + 2 Cots – $105

Restrooms are located on the property and available for use by runners throughout the event.

Rules and Etiquette

Start time are posted above and start promptly on time. If you arrive late for the start of your race you may still compete, but the time you’ve missed is lost and cannot be made up.

A pre-race meeting will take place 5 minutes before each event. At the start, you will begin circling the loop counter clockwise. Thereafter, you will change direction every six hours (at 2:00 PM, 8:00 PM, 2:00 AM, 8:00 AM, etc).

You may leave the course at any time. If and when you decide to continue, you must return to the course at the exact same place you left it, and complete the lap you were on when you stepped off the track, in the same direction as you were going, regardless of the direction other runners are moving when you return. This ensures that you are credited with the correct number of laps.

There are no DNFs in any of the multi-day runs and no drop-downs allowed. The objective in the multi-day runs is only to go as far as you can (or desire) in the allotted time. Of course, the more time you spend moving forward, the more distance you will accumulate.

If you wish to stop completely before the official end of your race, inform the race director or timing personnel, that you are quitting or leaving early and remember to turn in your chip!

An awards ceremony will follow shortly after the conclusion for all events at 8:30 AM on the last morning.

NO CUTTING THE CURVES. You must STAY OUTSIDE the cones or markers on the curves. The Estrella Mountain course is on a paved sidewalk. You may not cut the inside curve of the course, however there are a couple of stretches on the outside of the course that are dirt which you may run on. Nonetheless, if you cut the curves you will be disqualified.

It is your responsibility to know the rules. They exist to provide a good experience for all runners. If you are caught cheating you will be asked to leave and will not be allowed at future Aravaipa Running events.

Course etiquette does not require lone runners to yield the inside lane to runners wanting to pass, regardless of whether the one being passed is running or walking at the time. It is assumed that each participant is there to do his or her best, and has an equal right to pursue personal goals. In a race of this type, it is to be expected that even the best will walk for periods of time, particularly those in the longer races. Always pass others on the outside if they are on the inside lane.

An exception to this policy is the case of two or more persons running or walking together. Persons traveling around the trail in groups should always leave an inside channel open so faster runners do not have to travel far to the outside to get around them.

In all cases, remember to show common courtesy, and that most of us run for the enjoyment and thrill of the experience.

Medical

We will have an onsite EMT for the duration of the 48 hours of the event provided by MedStar Solutions. Please see them for any sort of health related questions or issues during the event.

Trash

Please respect Estrella Mountain Regional Park by disposing of any trash at our aid station or designated receptacles in the recreation area.

Results

2023

Photos

Podium Photos | 2023
KevLV Photography