REF-857 · Dindorf et al., 2025 · PLOS One, Vol. · Paper · PubMed

Exploratory analysis of critical event phases and the impact of team size and performance levels in 24 hour ultra cycling

Blimited evidenceMeasured on recreational to highly trained athletesWritten before October 2026, being re-checked

The authors took four straight years (2019-2022) of results from a 24-hour cycling race held on a 17.9 km road loop and analysed them with the current-to-final rank difference, which measures how far a rider's or team's rank at a given time is from the final rank. As the race went on, final standings grew steadily more predictable.

Solo riders had the least settled standings throughout, larger teams settled earlier, and medium-performance entrants (especially solo riders) stayed uncertain longer than high- and low-performance ones.

Participants

Entrants of one 24-hour race, 2019-2022: solo riders and teams of 4 and 10, riding laps of a 17.9 km road circuit. The numbers of riders and teams, and their sex and age, are not given in the abstract.

Protocol

Current-to-final rank difference (CFRD) computed through the race for each entrant.
Temporal trends in CFRD compared by team size (solo, 4, 10) and performance level (high, medium, low).

Key Results

Time, team size and performance level interacted significantly: F(18.04) = 1.74; p = 0.03.
Final standings grew steadily easier to predict as the hours went by.
Solo riders had the least settled final standing at every point of the race.
Larger teams saw a clearer picture of their final ranking at an earlier point of the race.
Medium-performance entrants, especially solo riders, show lower clarity across the race; high- and low-performance teams tend to show more predictable outcomes at earlier stages.

Practical Application

Over four editions (2019-2022) of one 24-hour race on a 17.9 km circuit, rank became more predictive of the final result as the race went on, but solo riders and mid-field entrants had the least settled standings throughout, while larger teams and the front and back of the field settled earlier (time × team size × performance interaction, p = 0.03). To "does my position at half-distance matter in a solo 24-hour race?": for a mid-field solo rider, much less than it seems — positions keep moving late in the race.
Inference, not tested here: for a solo rider in the middle of the field this argues for riding one's own sustainable plan rather than chasing places in the early hours, since early rank says little about the finish. The study measured ranks, not pacing, so it cannot say which pacing wins.
The abstract does not identify the critical event phases by hour; do not quote a specific time window from this paper.
Not from this paper; the base's own practice: how hard to ride as the hours pass and how to eat through the night are in SYNTH-63; a falling heart rate over a day-long race is described in REF-797.

Limitations

Exploratory analysis of one race on one circuit; sample size is not given in the abstract.
Rank data only: no power, heart rate, stops or nutrition, so the causes of rank changes are unknown.
The critical phases the title refers to are not described in the abstract.
Written from the abstract and record metadata only (full text not read).
How this entry was checked and changed
Why this level

exploratory results analysis of one race; the number of riders and teams is not given in the abstract