Running

Run a browser-local breathing pacer with custom inhale, hold, and exhale timing, live ring cues, phase charts, timeline history, and exports.

Plan race-week carbohydrate targets from body weight and event length, with daily grams, meal blocks, ramp timing, and gut-tolerance flags.

Plan run or ride fueling with carb, fluid, sodium, bottle, gel, and reminder targets that expose shortfalls before training or race day.

Calculate Friel heart rate zones from LTHR or field-test averages, with sport-specific bands, current-HR lookup, session planning, and exports.

Look up the Good VO2 max range for an adult age cohort and reference sex, then rate a measured value with source-table gap notes.

Calculate heart-rate zones from age, measured max HR, or heart-rate reserve, then compare formulas, current pulse, and session minutes.

Estimate a marathon finish time from weekly distance, training speed, and run frequency, with even-effort splits and caution checks.

Build a marathon training schedule from your race date and current base, then review long-run progression, cutbacks, taper weeks, and calendar exports.

Calculate VO2 max from heart-rate, Cooper, 1.5-mile, or Rockport test data with METs, absolute oxygen use, warnings, and age-sex benchmarks.

Convert running pace to speed or speed to pace, then estimate finish times, split checkpoints, and Riegel race projections in km or miles.

Build a race pace band from distance, target time, marker spacing, and pacing shape, with cumulative splits, strategy checks, and drift charts.

Estimate a race finish clock from distance, pace, or speed, then check split plans, pacing shape, planned stops, and cutoff margin.

Predict a race finish from a recent result, then compare Riegel pace, even splits, condition scenarios, and charted sensitivity.

Build a race pace plan from a target time, speed, prior race, or training block with split checkpoints, stop allowances, and scenario charts.

Track live race splits or paste stopwatch notes, compare pace by segment, and export charts, split ledgers, and summaries for post-race review.

Plan run-walk intervals from distance, segment paces, and marker stops, then compare finish time, cue load, route markers, and pace charts.

Calculate target heart-rate bpm from age or known max HR, compare %Max and Karvonen ranges, and check zones, windows, and current HR.