Event programsHybridRunningStrength
Tough Mudder 15K: 10 weeks, peaks at ~6 h.
About 9.3 mi and 20+ obstacles: less running pace, more cold water, grip and teamwork. That's the intermediate plan; beginner runs 10, advanced runs 10 weeks.
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The checklist comes with it.
Every plan cites its homework.
Durations are estimates: no official figure was found, so they are scaled from Spartan durations and from queueing at team obstacles (10–30 min for open waves). Tough Mudder's FAQ and training guide could not be read (403 / email-gated), so formats and obstacles come from its event pages and Wikipedia; whether obstacles are optional is not stated on any page read. Minimum runways are consensus. On-site injury rates at OCR events run at about 2.4% of participants, mostly lacerations and musculoskeletal (Rabb 2018). The Tough Mudder 10K is not on the 2026 US or UK calendars read; where one is offered the dossier scales this plan (long sessions to 70%, HY27 at 8 km), which isn't encoded.
- 1Helios research dossier — hybrid and obstacle events
- 2Tough Mudder — Nashville 2026 event page (formats, obstacle counts)
- 3Tough Mudder — obstacles
- 4Tough Mudder (Wikipedia)
- 5Rabb et al. 2018 — injuries at 33 Canadian obstacle-course races
- 6Eichner 2014 — Tough Mudder injury case reports
- 7Lessiohadi et al. 2024 — injuries in obstacle course racing (systematic review)
- 8Helios research dossier — event principles (fluid and sodium starting ranges, §8)
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Cycling
Gran Fondo
100–180 km mass-start sportive with 1,500–3,500 m of climbing: aerobic riding broken up by repeated 10–40 min climbs.
Cycling
Century
100 miles (160 km), mostly flat or rolling, ridden in groups: steady aerobic power, drafting and eating on the clock.
Cycling
Long Gravel — Belgian Waffle Ride / Unbound
Mixed-surface ultra-distance: hours of riding on gravel, sand and singletrack, timed KOM / KOD / sprint sectors, self-sufficiency between aid stations.
Cycling
Criterium
30–75 minutes on a short circuit with 4–8 corners: dozens of surges out of corners, soft-pedalling between, and a sprint.
Cycling
Time Trial
A solo effort against the clock over 16–40 km in the TT or aero position: even pacing at threshold, and the position you can hold.
Running
5K
5 km on the road or a parkrun: about 85–90% aerobic, run near 94% of threshold pace — VO2 and threshold work dominate the build.
Running
10K
10 km on the road at about 97% of threshold pace — for most runners close to threshold itself.
Running
Half Marathon
21.1 km at about 101–103% of threshold pace: threshold endurance, a long run near two hours, and fuel if you'll be out over 90 min.
Running
Marathon
42.2 km at about 104–108% of threshold pace: endurance, marathon-pace work, 60–90 g/h practised in the long runs, and a 3-week taper.
Running
50K Trail Ultra
50 km on trail with 1,000–2,500 m of climbing: time on feet, hiking the steep climbs, effort-capped for the first half.
Running
50 Miles / 100K Trail Ultra
80–100 km on trail with 2,000–5,000 m of climbing, usually into the night: Endurance-capped first half, 200–400 kcal/h, caffeine after halfway.
Running
100-Mile Ultra
161 km — mountain (5,000–10,000 m D+) or flat / loop — through one or two nights: at or below aerobic threshold early, front-loaded carbohydrate, caffeine at night.
Swimming
1.5 km Open-Water Swim
1,500 m in open water — essentially a threshold event: CSS is roughly 1500 m time-trial pace, plus sighting, starts and drafting.
Swimming
5 km Open-Water Swim
5 km in open water — an aerobic-capacity and pacing event, where losing technique late in the race is the usual failure.
Swimming
10 km Open-Water Swim
The marathon swim: 10 km in open water, decided by lactate threshold, even pacing and feeding on the move — often against a 4–5 h cut-off.
Rowing
2000 m Erg Race or Test
2,000 m on the rowing ergometer — 6 to 9 minutes in the severe domain, decided mostly by aerobic power and by pacing the first 500 m.
Swimming
Sprint Triathlon
750 m swim, 20 km bike, 5 km run in about 1–2 h: the bike near threshold and the run close to 5K effort.
Swimming
Olympic Triathlon
1.5 km swim, 40 km bike, 10 km run in 2–3½ h: the bike just under threshold and the run close to 10K effort.
Swimming
IRONMAN 70.3
1.9 km swim, 90 km bike, 21.1 km run in 4–8½ h: a capped-IF bike that protects the half marathon, and fuelling on the clock.
Swimming
IRONMAN
3.8 km swim, 180 km bike, 42.2 km run in 9–17 h: an IF-capped bike, 60–90 g/h of carbohydrate, and a marathon that decides the day.
Running
Duathlon (standard)
10 km run, 40 km bike, 5 km run in about 2–3½ h: a restrained Run 1, an Olympic-intensity bike and a strong Run 2 on loaded legs.
Swimming
Aquabike (70.3)
1.9 km swim and 90 km bike in about 3–5½ h, no run: a bigger swim share and a bike that can ride a little harder than in a 70.3.
Pickleball
Pickleball Tournament
A pickleball tournament — repeated 3–9 s rallies at about 1:1.6 work:rest, 3–6 matches a day, where tissue injury is a bigger risk than fatigue.
Tennis
Tennis Tournament
A tennis tournament — 5–10 s points at 1:2–1:4 work:rest, up to 2 matches a day over 2–3 days, with sprint, jump and serve accuracy falling from day 2.
Padel
Padel Tournament
A padel tournament — 9–16 s rallies at about 1:1, best-of-3 matches of 60–120 min with frequent overheads, 1–3 matches a day over 2–3 days.
Squash
Squash Tournament
A squash tournament — the most aerobically demanding racket sport (elite play near 92% of HRmax), best-of-5 matches of 40–90 min, 1–2 matches a day over 2–3 days.
Badminton
Badminton Tournament
A badminton tournament — ~7–10 s rallies at about 1:2 work:rest, 3 games to 21, and 3–6 matches in a day for a singles + doubles + mixed entry.
Athletics
Decathlon
Ten events over two days — the highest in-competition injury rate in athletics, and almost no research on how to train for it.
Athletics
Heptathlon
Seven events over two days, where the speed events — hurdles, high jump, 200 m and long jump — explain most of the score.
Hybrid
HYROX
8 × (1 km run + 1 station) — an aerobic race with repeated strength-endurance spikes, about half of it running.
Hybrid
Spartan Sprint
5 km and 20 obstacles on steep trail: grip-limited pass/fail obstacles, heavy mandatory carries, crawls and walls.
Hybrid
Spartan Super
10 km and 25 obstacles on steep trail: grip-limited pass/fail obstacles, heavy mandatory carries, crawls and walls.
Hybrid
Spartan Beast
21 km and 30 obstacles on steep trail: grip-limited pass/fail obstacles, heavy mandatory carries, crawls and walls — five or more hours on your feet for many.
Hybrid
Obstacle 5K / Mud Run
5 km with 10–15 obstacles — a Tough Mudder 5K, a charity mud run or a local obstacle 5K, mostly untimed or chip-timed without penalties.
Hybrid
CrossFit Open
Three weekly workouts, each a 10–20 min mixed-modal test — wall balls, box jump-overs, dumbbell work, pull-up to muscle-up ladders, burpees over the bar, cleans and thrusters.
Hybrid
Murph
1 mile, 100 pull-ups, 200 push-ups, 300 air squats, 1 mile — with a 14/20 lb vest for Rx. Usually done on Memorial Day, often in the heat.