Race Options
5K Run/Walk
Super Sprint Triathlon
300m swim / 23k bike / 2 mile run
Sprint Triathlon
750m swim / 23k bike / 5k run
Sprint Collegiate Triathlon
750m swim / 23k bike / 5k run
Sprint High School Triathlon
750m swim / 23k bike / 5k run
Sprint Aquabike
750m swim / 23k bike
Sprint Duathlon
2 mile run / 23k bike / 5k run
*NEW* - Sprint Aquathlon
750m swim / 5k run
Sprint Relay
750m swim / 23k bike / 5k run
Sprint Paratriathlon
750m swim / 23km bike / 5km run
Sprint Paratriathlon Relay
750m swim / 23km bike / 5km run
Olympic Triathlon
1.5k swim / 40k bike / 10k run
Olympic Aquabike
1.5k swim / 40k bike
Olympic Duathlon
5k run / 40k bike / 10k run
*NEW* - Olympic Aquathlon
1.5k swim / 10k run
Olympic Relay
1.5k swim / 40k bike / 10k run
Half Triathlon
1.2 mile swim / 56 mile bike /13.1 mile run
Half Aquabike
1.2 mile swim / 56 mile bike
Half Duathlon
5k Run / 56 mile bike / 13.1 mile run
*NEW* - Half Aquathlon
1.2 mile swim / 13.1 mile run
Half Relay
1.2 mile swim / 56 mile bike /13.1 mile run
Race Options
Registration includes a race t-shirt, finisher medal, live race results, race photos, awards for the top finishers and a post-race party with music, food and drinks! Additional items available for purchase.
FINISHERS SWAG
Registration includes a race long sleeve hooded t-shirt, finisher medal, live race results, race photos, awards for the top finishers and a post-race party with music, food and drinks! Additional items available for purchase.
2025 Race Swag
THANK YOU TO OUR RACE SPONSORS!
Ready for the race of the summer?
Foss Swim School
370 Lakeside Triathlon
SUNDAY, AUGUST 24, 2025
Join us for the 5th annual USAT sanctioned Foss Swim School 370 Lakeside Triathlon! This race begins with a beautiful beach start at 370 Lakeside Park. Enjoy the lake swim, scenic fast bike course on the country roads of St. Charles County and finish your race with a run on the flat park trails. We offer a variety of race options from a 5k run, super sprint or sprint for newbies, up to half distance!
Endurance Expo PACKET PICKUP & BIKE DROP
SATURDAY, AUGUST 23, 2025
LOCATION:
370 Lakeside Park, Corporate Pavilion
1000 Lakeside Park Drive
Saint Peters, MO US 63376
TIME: 12:00pm – 4:00pm
We encourage athletes to pick up your packet today and drop off your bike today instead of race day! You can leave your bike in transition; we will have security all night to keep it safe. Leave your gear at home, that comes with you race morning.
You CANNOT pick up someone else’s packet unless you are doing a relay. Make sure you bring your Photo ID and bike.
MANDATORY PRE-RACE TALK: 1:30pm and 3:00pm with Sally Drake from MSE Racing, Stephe Rebeck from Backyard Lifeguards & BYLG Sport and a USAT Official.
RACE PACKET:
There will be 5 specific items to be aware of -
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Wristband: There will be a wristband with your race number. These must be worn to access transition on Saturday and Sunday. If you misplace this band, you will need to secure a new one prior to entering transition.
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Timing Chip: You will receive your timing chip when you pick up your packet at the expo on Saturday. DO NOT FORGET THIS ON RACE MORNING. You will wear the timing chip on your left ankle with the chip portion facing out. This is how you will be timed. NO CHIP = NO TIME = NO RESULTS.
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Bike Sticker: place this on your bike, usually the seat post is the best place or the top tube.
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Helmet Sticker: place this on the front of your helmet.
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Race Bib: You are only required to wear your bib while you are on the run. It should always be forward-facing and visible. You can affix it to you using safety pins or a bib belt
HOW TO RACK YOUR BIKE:
You will rack your bike according to your race number. Look for your number at the end of each rack. Bikes must be racked in alternating directions, preferably by the seat.
ENDURANCE EXPO:
Allow time to visit -
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vendor booths
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athlete's lounge under the purple tent to participate in some onsite Yoga
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yard game section
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food trucks
370 Lakeside Park amenities for additional family fun –
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splash pad
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fishing
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small playground
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rentals - kayaks, paddle boards, paddle boats and bikes
RACE DAY & Finish Line Festival
SUNDAY, AUGUST 24, 2025
LOCATION:
370 Lakeside Park
1000 Lakeside Park Drive
Saint Peters, MO US 63376
TIME: 4:30am – 4:00pm
AGENDA & DESCRIPTION:
PARKING: There is a variety of parking around 370 Lakeside Park. The closest and most advantageous parking is the grass field directly next to the 370 Lakeside Corporate Pavillion. Please do not park in any other grass areas in the park. There will be volunteers directing athletes and volunteers to specific parking areas. Please follow their directions for parking and do not run them over :)
4:30am – Transition Opens – check in gear. Athletes only in the transition area, we will check your wrist band that you will find in your packet.
5:00am - 6:00am - onsite race day packet pickup.
5:00am – Wetsuit announcement – legal if water is 78 degrees or below. Not legal if it is over, and wetsuit optional if 78-82 degrees but this group will not be eligible for any awards or USAT points. 82 degrees or above – NO wetsuits allowed.
6:20am – Swim warm up or splash in if daylight allows
6:30am – Transition Closes – you will NOT be allowed back in. Athletes line up to start. Pre-race announcements
6:45am – Super Sprint Triathlon athletes begin, immediately followed by the para-athletes start!
7:00am – All other swim starts begin! Half, Olympic and Sprint athletes.
7:30am - 5K participants and Duathlon participants start. (NEW/EASIER). Please be in the starting corrals by the swim start by 7:15am.
SWIM START:
The 370 Lakeside Triathlon will start athletes in 4 waves: Half Wave, Olympic Wave Sprint Wave and Super Sprint Wave. You will seed yourself in your wave by your estimated 100-yard swim pace, we will have pace signs. Athletes in each wave will enter the water 4 at a time, every 5 seconds. Once the first wave of athletes are in the water, we will repeat this process with the second wave of athletes and then the third wave of athletes and then the fourth and final wave of athletes. The swim start plan will be discussed in detail at the highly recommended pre-race talk.
RACE CUTOFFS:
Sprint distance athletes have 3 hours to complete the Sprint distance triathlon.
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Swim must be completed under 30 minutes from athlete race start
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Bike must be completed under 2 hours from athlete race start
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Run must be completed under 3 hours from athlete race start
Olympic distance athletes have 4.5 hours to complete the Olympic distance triathlon.
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Swim must be completed under 1 hour from athlete start
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Bike must be completed under 3 hours, 15 minutes from athlete start
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Run must be completed under 4 hours, 30 minutes from athlete start
Half distance athletes have 8.5 hours to complete the half distance triathlon.
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Swim must be completed under 1 hour,10minutes from athlete start
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Bike must be completed under 5 hours, 30 minutes from athlete start
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Run must be completed under 8 hours, 30 minutes from athlete start
Race management reserves the right to remove an athlete from the course and DNF the athlete if course officials determine there is no possibility of an athlete finishing the given discipline (swim, bike, run) before the posted cut off times based on an athlete’s location, time, and average speed up to that point.
ON COURSE NUTRITION & DRINKS:
Please carry your own nutrition. Water and an electrolyte drink on the bike for the half distance athletes. Water and electrolyte drink on the run for all athletes.
BIKE SUPPORT: Our awesome sponsor, Granada will have a mechanic in transition for last-minute needs. Granada will also have a SAG vehicle on the course just in case you have an issue that you cannot fix during the ride.
FINISH LINE FESTIVAL: Food, drinks, vendors, and music under the pavilion! Invite family and friends! Athlete meals are included, and there is a small fee for non-athletes.
AWARDS: Listen for announcements. We will do the Sprint and Olympic distance awards as soon as the majority have finished, then Half distance awards in the early afternoon.
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Top 3 Overall Male & Female Awards for the following divisions: Super Sprint Triathlon, Sprint Triathlon, Sprint Aquabike, Sprint Duathlon, Sprint Aquathlon, Sprint Paratriathlon, Spint Highschool, Sprint Collegiate, Olympic Triathlon, Olympic Aquabike, Olympic Duathlon, Olympic Aquathlon, Half Distance Triathlon, Half Distance Aquabike, Half Distance Duathlon, Half Aquathlon, 5K Run/Walk
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Top 3 Age Group Male & Female Awards for the following divisions: Sprint Triathlon, Olympic Triathlon, Half Distance Triathlon
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The age group breakdown is standard 5-year age groups, 0-19, 20-24, 25-29, 30-34….75+
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Top 2 Age Group Male & Female Awards for the following divisions: Super Sprint Triathlon
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The age group breakdown is standard 5-year age groups, 0-19, 20-24, 25-29, 30-34….75+
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Top 3 Relay Teams for the following divisions: Sprint Relay, Olympic Relay, Half Relay
All participants will race based on their age as of 12/31/2025.
USAT INFORMATION:
USAT, or USA Triathlon, is the national governing body of the sport of Triathlon. Sanctioning an event through USAT means the race is provided insurance for its athletes, race coordinators, and volunteers. As a sanctioned triathlon, all athletes are required to either be an annual USAT member or purchase a one-day membership pass. If you are currently a USAT member, please make sure to bring your proof of membership when you pick up your packet. If you do not bring this proof, you will be charged the one-day membership fee. If you are not an annual member, you will need to purchase a one-day membership (to insure you as a triathlete) before you are able to pick up your packet. One-day membership will be collected when you register online.
A USAT Official will be at the event and will be enforcing all USAT rules. It is strongly suggested you visit the USAT website for the complete list of rules and review.
RACE SHIRT GUARANTEE: Last day to register to guarantee a race shirt is July 28, 2025.
INCLEMENT WEATHER & REFUND POLICY:
There is NO rain date, We Go Rain or Shine. In case of inclement weather,
management reserves the right to cancel/alter/modify the race/course for safety concerns. In any case there will be No Refunds of race entry fees. Each athlete must accept any such risk of their entry fee paid. There is no complementary race entry to a future race. All monies collected are used to develop and produce the event, including all race supplies, staffing, and administration. We pledge to make every effort to produce a fair, safe, and exciting event for all. Any decision we make to go forth with the race is based on the overall event safety.
We have a strict NO REFUND policy.
PHOTO DISCLAIMER:
There may be a photographer on site capturing pictures of the event. Since this is a public event, we reserve the right to post photos on our social media or agency website. Photos may also be used in promotional materials.
ADDITIONAL RELAY INFORMATION:
Relay triathlon is a WONDERFUL way to experience a triathlon if you are not ready to run the whole thing, if you are not capable of competing in a specific leg, or if you just want an opportunity to share something unique with friends or family. A triathlon relay can be done with 2 or 3 people. The team can consist of all male participants, all female or mixed. Each person does 1 or 2 legs of the race. The timing chip will have a Velcro strap on it and is handed off from one athlete to the next in transition. All athletes receive full swag and finisher medals.
SPECTATOR INFORMATION:
Spectators, the unsung hero of the triathlon. Without family and friends there to cheer us forward, the rigors of our sport would be far more difficult. MSE Racing is dedicated to ensuring that these vital portions of our triathlon family are given the opportunity to enjoy themselves while they wait for the next opportunity to see you fly by.
MSE Racing is proud to provide the following amenities:
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Sign making craft table for kids
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Yard game section
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Food options available for purchase so that spectators can have something to eat
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Music for additional entertainment
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Vendor and club booths available to visit
So, bring out those cow bells and noise makers for a fun day at the race!
LODGING INFORMATION:
Drury Inn & Suites - St. Louis | St. Peters
170 Mid Rivers Mall Circle
St. Peters, MO 63376
(636) 397-9700
The 370 Lakeside Triathlon Room Block Information:
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Start Date: TBD
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End Date: TBD
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Last Day to Book: TBD
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Our special group rate is: TBD