EIGHTPACE V16 — RESEARCH AND PRODUCT DESIGN NOTES 7 October 2026. Programme revision 7 remains unchanged; customer experience revision 16. WHAT CHANGED The advanced label previously checked entry criteria but did not preserve a reported weekly quality-running habit in week one. Recent weekly minutes did not meaningfully scale its opening easy work. V13 asks about continuity, familiar quality work and total recent running, and shows why the opening was selected. A time goal remains an aspiration, not permission to invent faster training paces. RESEARCH AND ITS LIMITS 1. Filipas et al. (2022), 60 trained male runners, 16 weeks, four sequences of pyramidal/polarised intensity distributions. Mixed intensity and its organisation can affect running outcomes. Population and training differ from HYROX. No universal 80:20 prescription or exact app dose follows from this study. https://pubmed.ncbi.nlm.nih.gov/34792817/ 2. HYROX performance across seven seasons (2026), observational PRO/ELITE competition analysis. Running and loaded stations warrant attention; association is not validation of a training plan. https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2026.1847569/full 3. Frandsen et al. (2025), prospective cohort of 5,205 runners. Single-session distance spikes relative to the recent longest run were associated with injury. This does not validate a universal weekly percentage, a minutes-based cap, or the app's 90%/70% choices. https://pubmed.ncbi.nlm.nih.gov/40623829/ 4. Schumann et al. (2022), systematic review/meta-analysis of 43 studies of concurrent endurance and strength training. Same-day training is not categorically unsuitable. Outcomes, order, fatigue and recovery matter. This is synthesis, not a direct HYROX intervention, and does not establish the exact combined sessions here. https://pubmed.ncbi.nlm.nih.gov/34757594/ AUTHORED IMPLEMENTATION CHOICES — NOT RESEARCH-VALIDATED DOSES Consistent recent training plus weekly controlled quality work and at least four consistent weeks allows an established intermediate/advanced athlete to retain controlled work in the opening week. That work is capped by their reported familiar minutes and 16/20 minutes respectively. Others receive an easier opening with a reason. These authored thresholds are in the current confirmed coach-review scope. Opening running uses a 90% recent-minute allowance for consistent training, 70% when returning/unknown, includes the full running warm-up allowance, and respects recent longest run and available time. Easy-work scaling is capped at 1.65 times the existing authored variant. Short combinations cap easy work at 30 minutes; long work caps at the reported longest run (max 75) initially. Later long-run ceilings can rise by up to ten minutes following the existing lighter-week shape. These are transparent product rules, not a validated injury-prevention algorithm. A large reduction from recent volume is flagged. Familiar controlled pace or a recent 5/10 km result can refine the estimated time needed for kilometre repetitions. They do not provide a laboratory threshold, predict fatigued running, or prescribe a goal pace. Without a reference, the duration is explicitly an estimate. Six repeats remain limited to the earlier established advanced five-day progression. Eight repeats are not assigned automatically. Quality running keeps its own day. Strength-first combinations pair lifting with easy running or station skills. Three-day routes alternate demands. Split sessions require opt-in and separate budgets. Recorded classes remain visible for load review; the app does not automatically compensate for them or optimise total load. Race date handling retains existing 6–12-week eligibility rules, a four-week base block for distant/undecided dates, a longer foundation route when needed, and review for dates too close for a supported block. It never compresses twelve weeks into an arbitrary deadline. GOAL-TIME SCENARIO The user may enter estimated total station and transition minutes. Required run pace = (target finish minutes - stations - transitions) / 8 km. This arithmetic is shown separately from workout effort. If it requires pace at least as fast as a fresh standalone running result, the app flags the mismatch; this is a prompt to review, not a validated feasibility prediction. PUBLIC PRODUCT REFERENCES Trainerize: calendar -> instructions -> tracking, clear rest timers and actual results. https://help.trainerize.com/hc/en-us/articles/208689026-How-do-I-use-the-mobile-app-when-I-m-working-out Stridist: public client-app presentation of workout guidance, history and check-ins. https://stridist.com/features/client-mobile-app/ Runna: public Today / Plan / progress navigation and workout detail guidance. https://support.runna.com/en/articles/10473504-your-quick-guide-to-navigating-the-runna-app MARCHON: public programme overview separates running, lifting, rest and hybrid work. It is a coaching example, not proof of one optimal schedule. https://online.marchon.co.uk/programs/hyrox No paid programmes were accessed. Content and interface were authored for Eightpace. No measured conversion or retention improvement is claimed. PRODUCT APPLICATION One next action on Today; selected week first in Plan; main targets, effort, recovery and duration in each session; a visible explanation of the starting workload; library browsing separate from training assignment; actual results and partial sessions in Progress. Quiet milestones reward record keeping and recovery, not extra workload. The homepage shows actual screenshots, a clear seven-day trial / £9.99 monthly offer, and honest scope instead of invented testimonials or urgency. LIMITATIONS Self-reported input may be mistaken. The app does not measure physiology, assess technique, diagnose injury, establish medical clearance, or guarantee a finishing time. No real-user retention/conversion study has yet validated these changes. Software tests do not constitute coaching approval. The operator has confirmed current rules were reviewed by their certified HYROX trainer; this is not an independent credential audit or a claim of clinical validation. V16 RESEARCH AND ATHLETE CONTEXT The July 2026 seven-season HYROX study is observational PRO/ELITE competition analysis. Running is approximately half of overall race duration. Its close association with total time partly reflects that running time is included in total time; the paper also analyses this mechanical contribution. Loaded stations matter, and the findings do not justify reducing every athlete's preparation to running alone. They cannot establish individual doses for adult Singles Open. https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2026.1847569/full Hunter McIntyre's first-person account of preparation for Dallas describes stacking race-pace work and demanding strength-endurance work, insufficient separation and injury. This is practical athlete context, not controlled research, and is not evidence for copying a champion's volume or attributing an injury to one cause. We use it to illustrate why the whole week's demands matter. No supplement recommendation is adopted from the source. https://bldrsports.com/blogs/what-is-bought-in/double-down-for-dallas CURRENT PUBLIC PRODUCT COMPARISON Runna: clear trial offer, goal/experience-led setup and recognisable product screens. https://www.runna.com/ RMR Training: public programme selection uses training time and separate base/foundation/race contexts. https://www.rmr.training/rmr-app MARCHON: public hybrid-training programme presentation. https://online.marchon.co.uk/programs/hyrox Trainerize and Stridist: public workout instructions, tracking and client app examples, linked above. These are qualitative interface references. We have not measured competitors' conversion rates, verified a highest-performing ranking, or accessed their paid plans. Seven days then £9.99/month is the operator-approved launch hypothesis, not a proven conversion optimum. Measure eligible preview-to-checkout, activation, first useful workout, cancellation and retained paid use before making outcome claims. V16 APPLICATION Keep one primary start-trial action and one sample-plan secondary action. Show card requirement, renewal amount and cancellation together. Preview the plan before checkout. Use actual app screens; remove decorative training photographs from the main landing, login, Today and Learn paths. Weekly summaries follow moved workout dates. A cancelled checkout resumes the saved confirmed plan. Membership enforcement exists on server writes and workout entry; saved records remain readable after access ends. Quiet milestones recognise recorded progress and recovery, never extra exercise. CURRENT LIMITS No watch/GPS integration, validated finish-time prediction, automatic class-load optimisation or measured retention/conversion uplift. No changes to training prescriptions are made in this release. Physical-phone and real-customer testing remain separate from automated checks and browser viewport testing.