How accurate are the RunBikeCalc calculators?

RunBikeCalc calculators use validated sports science formulas: the Jack Daniels VDOT system for running pace zones, the 95% of FTP standard for cycling threshold power, and the Karvonen formula for heart rate zones. Results are accurate within ±3-5% for most athletes under normal conditions. Individual variation from lab-tested values is expected — use calculator results as a starting baseline, then adjust based on how you actually feel at those intensities during training. For racing, always verify paces in training before committing to a race plan.

What is the difference between heart rate zones and power zones?

Heart rate zones (typically 5 zones based on max HR or lactate threshold HR) reflect cardiovascular effort — useful for all endurance activities. Power zones (7 zones based on FTP) measure actual work output in watts — available only on bikes with power meters. Power zones respond immediately to effort changes; heart rate lags 30-90 seconds. For steady-state riding, both methods produce similar training stress. For intervals, power is more precise. Beginners should start with HR zones (cheaper, sufficient); serious cyclists wanting performance data should invest in a power meter.

How do I find my FTP (Functional Threshold Power)?

The most common FTP test: warm up 20 minutes, then ride all-out for 20 minutes, take 95% of your average power as your FTP. Alternative: the 8-minute test (2 × 8 minutes all-out, rest 10 minutes between, take 90% of the higher effort's average power). Ramp tests (increasing power every minute until failure) are popular on smart trainers and typically correlate to within 5-10% of traditional FTP tests. FTP typically improves 10-20% in the first training year and 3-5% annually for experienced athletes. Retest every 6-8 weeks during a training block.

Build Your Home Gym

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Home Gym FAQ

Power rack vs squat stand - which should I buy?

A power rack (full cage) provides four uprights with built-in safety bars, making it the safest option for solo lifting. A squat stand uses two independent uprights, takes less space, and costs less - but offers no built-in safeties unless you add spotter arms. Choose a full rack if you bench press alone or lift heavy. A squat stand works well if space is tight and you have a spotter or plan to add safety arms.

How much should I spend on a home gym?

A solid starter home gym (rack, bench, barbell, and 300 lb of plates) can cost $800-$1,500 total with budget-friendly brands like Titan or Fitness Reality. Mid-range setups with REP or Bells of Steel run $1,500-$3,000. A premium Rogue setup can exceed $4,000. Your rack is the centerpiece - spend 30-40% of your total budget there and build out accessories over time.

What ceiling height do I need for a power rack?

Most full-size power racks are 82-93 inches tall. For comfortable overhead pressing inside the rack, add at least 12 inches above the rack height. An 8-foot ceiling (96 inches) works for most racks under 84 inches. For taller racks (90+ inches) or overhead pressing, you need 9+ foot ceilings. Short-height and adjustable racks are available for basements with 7-foot ceilings.

Do I need to bolt my power rack to the floor?

Flat-foot racks (like the Titan X-3 Flat Foot or Rogue RML-390F) are designed to be stable without bolting, making them ideal for garage gyms. Standard four-post racks should be bolted down for safety during heavy squats, pull-ups, or muscle-ups. If you cannot bolt, use a flat-foot design or add heavy weight storage pegs at the base for extra stability.

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The gear these numbers assume

Every pace, zone and power figure on this page assumes something is measuring it. These are the three that cover running, cycling and the threshold work in between.

Garmin Forerunner 965

Multisport with the training-load and threshold metrics most of these calculations assume you can actually see day to day.

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COROS APEX 2 Series GPS Watch

Sapphire titanium and the longest battery in its class, which is the deciding feature once sessions run past a few hours.

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Favero Assioma Uno Power Meter Pedal

Single-sided pedal power, the cheapest honest way to start training with watts instead of estimating from heart rate.

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