Chelsea
Sodaro
Training Blueprint
Neal Henderson · Coach Ironman World Champion 2022 Ironman NZ Winner + Course Record 2024 Former USA 10K National Record Holder Boulder, Colorado
~20
hrs / current week
~25
mi run / week (building)
5–6
hrs long ride (Ironman build)
swims / week

Typical Training Week — Current Build Phase

Swim
Bike
Run
VO2 / High intensity
Down week / Recovery
Rest / Easy
MON
Julie Dibbins squad swim
Easy run 30–40 min
Low load day
TUE
Julie Dibbins squad — VO2 short intervals
Big gear / low cadence bike work
Easy run or rest
WED
Key bike: micro-intervals or VO2 (2.5 min / 1 min into Z3)
Easy run 30–40 min
THU
Julie Dibbins squad
Key run — fartlek / speed / threshold
Easy spin 45–60 min
FRI
Rest or easy swim
Easy run 30 min (optional)
SAT
Long ride — 3–4 hr (building to 5–6 hr Ironman block)
Easy 20–30 min off bike (when appropriate)
SUN
Long run or easy run
Full rest or easy swim

Chelsea's week under Neal Henderson is deliberately non-rigid — the schedule is not fixed to a seven-day cycle. Sessions are sequenced based on readiness and specific stimulus goals. Hard days are genuinely hard, easy days are genuinely easy. One high-intensity session per sport per week. Down weeks built in regularly, not just before races.

The Down Week — Chelsea's Most Underused Tool (Now Built In)

Under Dan Plews, Chelsea never took a formal down week unless it was taper or post-race. Under Neal Henderson, down weeks are now programmed regularly — not as a response to fatigue, but as a proactive recovery tool. "I take down weeks now that are quite chill." Neal's view: "Tolerating something to me does not mean high performance. What I look for is adaptation and improvement." A week of lower volume every 3–4 weeks allows the body to absorb the preceding hard weeks, preventing the chronic fatigue cycle that derailed Chelsea's 2023–24 period.

Dan Plews Era vs Neal Henderson — What Changed

Chelsea is emphatic that Dan Plews was the right coach at the right time — they won a world title together. But by 2024, the approach had run its course. Here's exactly what changed.

Dan Plews era

Volume approachConsistently high, no real dips
Down weeksOnly before/after races
Intensity rangeUpper aerobic dominant
Top-end work"Trained out of me"
Swim environmentOften solo
Coach locationOceania — large time diff.
Run sessionsHigh volume, incl. 30K long runs
Long ride frequencyFixed once per week

Neal Henderson era

Volume approachPeriodised — hard blocks + down weeks
Down weeksProgrammed regularly, not reactive
Intensity rangePolarised — very hard AND very easy
Top-end workActively restored — 1 VO2 session per sport/week
Swim environmentJulie Dibbins squad 3× weekly
Coach locationBoulder — in-person, same time zone
Run sessionsLower total volume, speed-focused (~25 mi/wk now)
Long ride frequencyFlexible — every 10 days, when appropriate

Intensity Distribution — Neal Henderson Model

Henderson's approach is explicitly polarised. "The hard is really hard and I am asked to be very disciplined when I'm going easy." One high-intensity session per sport per week is the cap. The rest is long, steady aerobic work. This is a direct departure from the upper-aerobic zone that dominated Chelsea's Plews-era training.

Easy / Aerobic — 60%
Threshold / Long efforts — 25%
VO2 / High intensity — 10%
Down week — 5%
1 VO2 session per sport per week (max) · Long ride: 5–6 hr (Ironman build) · Run: ~25 mi/week building · Swim: Julie Dibbins squad 3× · Long efforts 40–60 min in peak Ironman block · Lactate testing used regularly to calibrate zones

Chelsea's Exact Key Sessions

Every session below sourced from Chelsea's own words in the podcast and from Neal Henderson's published coaching methodology. These reflect her early 2025 build leading into a Kona target in October.

Bike — VO2 / Micro-Intervals One per week · Key bike session

~1 min at VO2max into 1–1.5 min at Zone 3 · Multiple sets

Chelsea's key bike intensity session under Neal Henderson. Short VO2max efforts (~1 min true max effort) immediately blending into a sustained Zone 3 effort — the "1 min into Zone 3" format. Henderson describes these as micro-intervals. The contrast with her Plews-era sessions is stark: she previously cried on the garage floor during 3–5 minute VO2 efforts in January. "Now I feel like I could do a couple more intervals — I'm not throwing up during these workouts." The session is calibrated to the season: not maximal, but hard enough to restore top-end capacity. Followed by regular lactate field testing to confirm zones.

Effort format
~1 min VO2 + 1–1.5 min Z3
Sets
Multiple (not to failure)
Frequency
1× per week max
Feel check
"Could do a couple more"
Monitoring
Lactate tested regularly
Bike — Big Gear / Low Cadence Off-season / winter · Building pedal efficiency

Low cadence, high torque work · Single-leg drills · Pedal stroke correction

Neal Henderson's first major addition to Chelsea's bike training. "No one ever taught me how to pedal a bike." Low cadence big gear work and single-leg drills are teaching Chelsea pedal stroke mechanics she never had — something Henderson has used with Taylor Knibb and Flora Duffy to develop cycling efficiency. Short sessions working on cadence and high-cadence turnover as well. "I'm really interested to see how it impacts my efficiency as we get into the meat of the season." This is the foundational investment that pays dividends when the longer threshold efforts come in later blocks.

Focus
Pedal stroke + torque
Drills
Single-leg, high cadence
Session length
Short (skill-focused)
Context
Never done before
Bike — Peak Ironman Long Ride Ironman specific block · Every 10 days (not fixed weekly)

5–6 hour long ride · Not fixed schedule · Lactate field testing en route

Chelsea's peak Ironman long ride under Henderson is 5–6 hours — similar to her Plews era. But the key change is frequency: previously one fixed long ride per week, now "every 10 days or something — the schedule is not so fixed." Neal followed Chelsea on an e-bike two weeks out from Kona 2025, stopping every 1.5 km to take a lactate sample to assess her "breaking point" in real time. This kind of field testing shapes the next training block precisely rather than relying on fixed targets. Chelsea says: "Nobody gets a benefit from having done the most hours before a start line. It's who can perform on the day."

Duration
5–6 hr (Ironman block)
Frequency
Every ~10 days
Testing
Lactate every 1.5 km (field)
vs old
Was fixed weekly
Run — Peak Ironman Intervals Ironman-specific block · Daunting but achievable

40–60 minute sustained intervals · "Insane" but doable when fit

Chelsea's favourite session when truly fit and in Ironman block — long sustained intervals of 40–60 minutes. "It's daunting, but you know you can do it, and you're going to feel really accomplished when you get it done." These are the sessions that define Ironman run fitness. Not short intervals — a sustained effort at threshold or sub-threshold that mirrors the demands of the marathon run. Currently she is only running ~25 miles per week with "really cruisy running" and some fartlek. These big intervals are the destination, not the current state.

Effort duration
40–60 min sustained
Context
Ironman peak block only
Current run vol.
~25 mi/week building
Feel
Masochistic joy
Swim — Julie Dibbins Squad 3× per week · 9 am · Boulder squad

Squad sessions · Short VO2 intervals · Community accountability

Chelsea swims with Julie Dibbins' squad in Boulder three times per week. The squad format is a major change from her previous solo swimming — "it's relieved a lot of the mental motivation that goes into training by yourself." The current focus is short VO2 max intervals in the pool with a good crew: "we all go off the same send-off and you can race each other, which has been really fun." Chelsea doesn't have to think about it — she shows up at 9 am, does the session, and leaves. The simplicity of this structure removes the decision fatigue of solo training and provides consistent community accountability.

Frequency
3× weekly
Time
9 am
Current focus
Short VO2 intervals
Key benefit
Community + accountability
Down Week Every 3–4 weeks · Programmed proactively

Significantly reduced volume · All sessions genuinely easy · Full absorption

The most structurally important element of Chelsea's new program — and the thing most absent from her previous training. "Before I would never have taken a down week unless it was before or after a race." Now, down weeks are programmed proactively, not reactively. Neal Henderson's principle: "Tolerating something does not mean high performance. I look for adaptation and improvement." The down week is when training adaptations are locked in. Without it, the training stimulus accumulates without being absorbed — the exact trap Chelsea was in throughout 2023 and 2024.

Frequency
Every 3–4 weeks
Approach
Proactive, not reactive
Volume reduction
Significant
vs old
Never done unless forced

4-Week Training Block — Ironman Build

Built from Chelsea's own description of her Neal Henderson program and his published coaching methodology. Week 3 is a hard peak week. Week 4 is a down week — not a taper, but a full absorption week. This pattern repeats throughout the season. The hard weeks are harder for the down weeks existing, and vice versa.

W1
Build — Introduce quality, restore top-end range
Low cadence bike · VO2 swim · Easy run volume building
~18–20 hrs
MON
Julie Dibbins squad swim at 9 am — "I show up, do the session, and leave." Easy 30–40 min run. This is the simplest day of the week. The squad accountability means Chelsea doesn't have to find motivation for the swim.
TUE
Swim (key): Julie Dibbins squad — short VO2 interval set, racing off the same send-off as the group. Bike: Big gear / low cadence work — Neal Henderson's pedal stroke correction sessions. Short, skill-focused, not fatiguing. Run: Easy 30 min jog.
WED
Bike (key — VO2): Micro-interval session: ~1 min VO2max into 1–1.5 min Zone 3, repeated. "The hard is really hard." Chelsea should feel challenged but not destroyed. Neal's calibration: "I feel like I could do a couple more intervals." Run: Easy 30–40 min after or the same evening.
THU
Swim: Julie Dibbins squad. Run (key): Fartlek or speed session — "a little fartlek or some speed" is what Chelsea currently enjoys on the run. Not a structured track workout yet, but playful, engaging quality. Bike: Easy 45–60 min recovery spin.
FRI
Rest or easy swim. Optional easy 30 min jog. This rest day protects the quality of Saturday's long ride. Chelsea's new program is explicit: easy days are genuinely easy, not moderate. "I am asked to be very disciplined when I'm going easy."
SAT
Bike: Long ride 3–3.5 hr at aerobic pace. Current building phase — not yet at the 5–6 hr Ironman peaks, but establishing the long-ride habit. Building toward that every-10-days rhythm. Pedal stroke and efficiency cues carried over from Tuesday's low cadence work.
SUN
Run: Easy long run 60–70 min. Chelsea is "really cruisy running right now" — ~25 miles per week is the current target. No pressure on pace or distance. Just time on feet and the joy of running, which she is rediscovering after a year of hating most sessions.
Coach cue — Week 1

Neal Henderson's first step with Chelsea was performance testing — lactate, pace, and power baselines — before writing a single session. "Testing early is about identifying the intensity dial and getting it calibrated effectively, because you don't want to just train where you were." The testing-first approach is what allows the micro-intervals to be hard enough to stimulate adaptation without tipping Chelsea into the overreaching cycle that damaged her in 2023–24.

W2
Load — Extend the long ride, increase run quality
Longer bike · Run threshold introduced · VO2 maintained
~20–22 hrs
MON
Julie Dibbins squad swim at 9 am. Easy 30–40 min run. Same recovery Monday rhythm — this consistency is part of the program's design. Chelsea knows exactly what Monday looks like and doesn't have to decide anything.
TUE
Swim: Julie Dibbins squad — VO2 intervals, slightly extended from Week 1. Bike: Progressed low cadence session — slightly higher power or more reps. Run: Easy 30–40 min. The pattern is steady: skill/strength on Tuesday, key intensity on Wednesday.
WED
Bike (VO2 maintained): Same micro-interval format — 1 min VO2max into Z3. Neal calibrates weekly from lactate data. The session should still feel like "could do a couple more" — if it feels maximal, the prescription needs reviewing. Run: Easy 30–40 min.
THU
Swim: Julie Dibbins squad. Run (key — threshold introduced): Short tempo intervals or a sustained threshold effort. Chelsea loves when there is "a little speed" in the run. This is the beginning of the structured run quality that builds toward the 40–60 min Ironman intervals later in the season. Bike: Easy spin.
FRI
Rest or very easy swim. The long Saturday ride benefits from fresh legs. Chelsea's previous mistake: not protecting these easy days properly. Under Neal, this is enforced.
SAT
Bike (extended): Long ride 4–4.5 hr with some race-specific blocks. Extending from Week 1's 3–3.5 hr. Not yet peak Ironman volume but building toward it. Neal may ride alongside or send ahead on an e-bike to take lactate at intervals on this kind of session.
SUN
Run: Long easy run 70–80 min. Slight extension from Week 1. Still easy — the long run is a volume accumulator, not a quality session. Chelsea's run background means pace is naturally fast even when easy. 25+ miles for the week.
Coach cue — Week 2

Chelsea's Kona 2022 win on a 6-week build is the counter-intuitive lesson at the heart of this program. "The mistake was, now that you're more healed from childbirth, we can push even more — when I probably nailed it the first time." Short, concentrated, well-rested builds outperform long exhausting ones for Chelsea. The 2022 Kona victory proves it. Neal's job is to recreate that stimulus deliberately rather than by accident.

W3
Peak — Hard week, genuinely hard, then absorb
Peak long ride · Threshold run · All intensity sessions at full output
~22–24 hrs
MON
Julie Dibbins squad. Easy run 30 min. This Monday rhythm is non-negotiable even in a peak week — it protects the quality of the hard days that follow.
TUE
Swim: Julie Dibbins squad — hardest swim session of the block. Bike: Peak low cadence / big gear work or progressed skill session. Run: Easy run to flush legs for Wednesday.
WED
Bike (peak VO2 session): Chelsea's VO2 micro-intervals at their hardest. "The hard is really hard." This is the session where she pushes close to her current limit — not quite "throwing up," but genuinely difficult. Lactate checked afterward. Run: Easy 30 min only.
THU
Swim: Julie Dibbins squad. Run (peak threshold): Sustained effort — building toward those 40–60 min Ironman intervals. This week might feature the first 20–30 min sustained threshold effort of the block, confirming fitness is tracking. Bike: Easy spin.
FRI
Rest. A proper rest day before the peak long ride. Chelsea knows the consequences of not resting here — she's been in the chronic fatigue cycle before. "I needed to really shut it down."
SAT
Bike (peak long ride): 5–5.5 hr ride at aerobic pace with targeted intensity blocks. Neal may conduct lactate field testing every 1.5 km on final build rides. This is the cornerstone of Ironman preparation. "I'll go between five and six hours." Easy 20 min run off the bike if appropriate.
SUN
Run: Long easy run 80–90 min. Tired legs from Saturday's big ride — that's the point. The combination of a long bike and a long easy run the next day creates meaningful Ironman-specific fatigue. All easy effort — the quality comes from cumulative load, not pace.
Coach cue — Week 3 (peak)

Chelsea describes the feeling she is rebuilding: "In the past I've looked forward to those insane intervals that are 40–60 minutes long in a masochistic type way — you know you can do it and you'll feel really accomplished." The goal of this week is to engineer that feeling — hard enough to feel heroic, not so hard that it breaks confidence or accumulates debt. Neal's calibration: if Chelsea feels like she "could do a couple more" at the end of the VO2 session, the prescription is correct. If she is lying on the floor, it's too much.

W4
Down week — Absorption, rest, and reset
Significantly reduced volume · All sessions easy · No intensity sessions
~12–14 hrs
MON
Easy swim at Julie Dibbins squad (optional — go if it feels good). Easy 30 min jog. No pressure on either. The down week starts with the same rhythms but zero obligation to perform.
TUE
Easy swim only — no intensity set. Easy 30 min bike spin. Easy 20–30 min jog. Everything easy. "My down weeks are quite chill." Neal's view: the down week is not a taper. It is a deliberate training tool that makes the following three hard weeks more productive.
WED
No key bike session. Easy ride 60–75 min only. Easy run 30 min. This is the day that previously would have been Chelsea's hardest of the week. Under Neal, it is now the easiest. "Before, I would never have taken a down week unless it was before or after a race."
THU
Easy swim squad. No run intensity session. Short easy run 20–30 min only. The body is processing the previous three weeks of hard work. Trying to push here would disrupt that process.
FRI
Rest or very easy swim. Some family time, some rest. Chelsea on the importance of her role outside triathlon: "I have to be very committed and have conviction because I don't have time to waste." The down week protects the personal energy bank as much as the physical one.
SAT
Easy 2–2.5 hr ride only. No intensity. Maybe a coffee ride with the Boulder community. This is why Boulder is a great base for Chelsea — there is always someone to ride easy with, at any level, any day.
SUN
Easy 45–60 min run. The block is complete. By Sunday, the body should feel noticeably better than Thursday — the adaptation is arriving. Next week, the hard weeks resume, and they will be better for this week existing.
Coach cue — Week 4 (down week)

Neal Henderson's most important coaching statement: "Tolerating something to me does not mean high performance. What I look for is adaptation and improvement." The down week is where improvement actually happens — in the rest and recovery after the hard weeks, not during them. Chelsea's 2023–24 chronic fatigue cycle was caused by never having these weeks. The training debt accumulated without ever being repaid. Every coach applying this model should treat the down week as sacred — not optional, not reactive, not shortened when the athlete feels good. It is the mechanism that makes everything else work.

Why It Works — Coaching Keynotes

Chelsea Sodaro's blueprint is a story of recovery, recalibration, and rediscovering joy. These keynotes come directly from her own words and from Neal Henderson's published coaching philosophy. They speak to the hardest lesson in endurance sport: doing less is sometimes the hardest and most courageous thing an athlete can do.

01 · PeriodisationDown weeks are not weakness — they are the mechanism of adaptation
The single biggest change in Chelsea's program is the programmed down week. "Before I would never have taken a down week unless it was before or after a race." Neal Henderson's principle: "Tolerating something to me does not mean high performance. What I look for is adaptation and improvement." The training stimulus is applied in the hard weeks. The adaptation is locked in during the down week. Without the down week, training debt accumulates silently until the body forces a shutdown — which is exactly what happened to Chelsea in 2023–24. For coaches: if your athlete has no scheduled down weeks, they are not periodising. They are managing fatigue. These are different things.
02 · Minimum effective doseThe goal is to win the race, not to win training
Chelsea articulates this better than almost any athlete in this series: "The goal is not to be a champion in training. The goal is to win races." Her 2022 Kona win came off a 6-week build post-pregnancy — lighter, fresher, hungrier than anyone expected. The mistake was to respond to that result by doing more. Neal Henderson's approach is the inverse: identify the minimum effective dose that produces adaptation, then apply it precisely. "Nobody gets a benefit from having done the most hours before a start line. It's who can perform on the day." For coaches: the athlete who arrives at the start line 95% cooked and fired up beats the athlete who arrives at 110% and is already fatigued.
03 · Bike developmentElite runners often have fundamental cycling skill gaps — address them directly
Chelsea came from a professional running background and transitioned to triathlon in 2017. Despite years of triathlon training, no one had ever taught her proper pedalling mechanics. Neal Henderson's response: short sessions on pedal stroke, single-leg drills, high and low cadence work — technical cycling skill that Chelsea had never had. "I'm really interested to see how it impacts my efficiency." This is the kind of marginal gain that a coach with Henderson's cycling background identifies that a running-focused or triathlon-generalist coach might miss. Former runners in triathlon often have this gap. It is correctable, but only if a coach looks for it.
04 · Run identityA world-class runner background is an asset — but not the focus
Chelsea is a former USA national champion at 10K and 3000m. Her run is arguably the strongest in women's Ironman racing when she is healthy. Under Neal Henderson, the run is intentionally not the focus right now: "I'm only running 25 miles a week or so — there's nothing too major or thrilling." This is deliberately conservative. The run does not need development — it needs preservation and freshness. Chelsea's quote: "I have a lot of confidence in all three sports when I'm healthy. When I've been healthy at the Ironman World Championships, I've won." The job is to arrive healthy, not to arrive with the fastest run training block of all time.
05 · CommunitySquad training removes the biggest barrier to solo training — motivation
Chelsea now swims with Julie Dibbins' squad three times per week. The impact is structural, not motivational: "I know I'm swimming with Julie three times a week at 9 am. I show up and do the session and leave and I don't think about it anymore." The decision about whether to swim is removed. The accountability is external. The motivation is social. This is a fundamental improvement over her previous solo swimming setup — where the mental energy required to motivate herself for sessions was being drawn from the same bank used for everything else. For coaches: if your athletes train solo, find them a squad for at least one discipline. The mental load reduction is performance-enhancing.
06 · JoyIf you are not excited to train 3–4 days a week, something is wrong
Eric Lagerstrom's advice to Chelsea, which she quotes as one of the most important things she was ever told: "If you're not totally stoked on your training 3–4 days a week, you're not doing this right." In 2024, Chelsea was excited for "hardly any sessions at all." Now she wakes up looking forward to almost every session. This is not accidental — it is the direct result of a better-matched program, a more engaged coach relationship, a training community in Boulder, and the structural rest that down weeks provide. Training joy is a leading indicator of performance. If athletes hate their training consistently, performance will follow downward. Protect the joy.
07 · Concentrated buildsA great 6-week build beats a mediocre 12-month grind
Chelsea's 2022 Kona win is the most important data point in her career: she won the world championship off a 6-week build coming back from pregnancy — fresher, lighter, and more motivated than anyone expected. Her insight now: "I actually believe because of my body of work throughout my entire career, I don't need months and months to get fit. I need a really solid concentrated 6-week-long block, and sometimes it's better to have that pressure because you don't have time to overthink it and overdo it." This is the paradox of professional endurance sport: the athlete who has accumulated a decade of training base does not need to build from scratch every season. They need to arrive at their key race fresh and sharp, not exhausted by 10 months of trying to be as fit as possible.

Data Sources

All training data in this blueprint is sourced from the athlete's own public statements, verified interviews, and published race data. Nothing is inferred or fabricated.

Primary Source

The Triathlon Hour (2025) — Chelsea Sodaro Interview

The primary source for this blueprint. Chelsea describes training philosophy, methodology, key sessions, and race preparation in their own words. All quoted material and specific numbers in this blueprint trace directly to this interview.

Supporting Source

Supplementary Research — Published Race & Training Data

Race results, split data, and training context cross-referenced from published race data. Used to verify the plausibility of stated training numbers and to contextualise the athlete's competitive trajectory. No training data comes solely from this source without primary-source corroboration.