Cycling Heart Rate Zones Calculator

Age:

Estimated Max Heart Rate (bpm):

Resting Heart Rate (bpm):

.cycling-heart-rate-calculator { font-family: sans-serif; border: 1px solid #ccc; padding: 20px; border-radius: 8px; max-width: 500px; margin: 20px auto; background-color: #f9f9f9; } .cycling-heart-rate-calculator h2 { text-align: center; margin-bottom: 20px; color: #333; } .input-group { margin-bottom: 15px; display: flex; align-items: center; justify-content: space-between; } .input-group label { margin-right: 10px; flex-basis: 50%; text-align: right; color: #555; } .input-group input { padding: 8px; border: 1px solid #ddd; border-radius: 4px; width: 50%; box-sizing: border-box; } .cycling-heart-rate-calculator button { display: block; width: 100%; padding: 10px 15px; background-color: #007bff; color: white; border: none; border-radius: 4px; cursor: pointer; font-size: 16px; margin-top: 15px; } .cycling-heart-rate-calculator button:hover { background-color: #0056b3; } .results { margin-top: 25px; border-top: 1px solid #eee; padding-top: 15px; color: #333; } .results h3 { margin-bottom: 10px; color: #444; } .zone { margin-bottom: 8px; padding: 5px; background-color: #e9ecef; border-radius: 4px; } .zone span { font-weight: bold; } function calculateHeartRateZones() { var age = parseInt(document.getElementById("age").value); var maxHeartRateInput = document.getElementById("maxHeartRate").value; var restingHeartRateInput = document.getElementById("restingHeartRate").value; var maxHeartRate; var restingHeartRate; if (isNaN(age) || age <= 0) { alert("Please enter a valid age."); return; } // Calculate estimated Max Heart Rate if not provided if (maxHeartRateInput === "" || isNaN(parseInt(maxHeartRateInput)) || parseInt(maxHeartRateInput) <= 0) { maxHeartRate = 220 – age; } else { maxHeartRate = parseInt(maxHeartRateInput); } // Get Resting Heart Rate if provided if (restingHeartRateInput === "" || isNaN(parseInt(restingHeartRateInput)) || parseInt(restingHeartRateInput) <= 0) { restingHeartRate = 0; // Set to 0 if not provided, to not affect Karvonen formula } else { restingHeartRate = parseInt(restingHeartRateInput); } var resultsDiv = document.getElementById("results"); resultsDiv.innerHTML = ""; // Clear previous results if (maxHeartRate 0 && restingHeartRate < maxHeartRate) { var heartRateReserve = maxHeartRate – restingHeartRate; zones["Zone 1 (Very Light) Karvonen"] = { lower: Math.round(restingHeartRate + (heartRateReserve * 0.50)), upper: Math.round(restingHeartRate + (heartRateReserve * 0.60)) }; zones["Zone 2 (Light) Karvonen"] = { lower: Math.round(restingHeartRate + (heartRateReserve * 0.60)), upper: Math.round(restingHeartRate + (heartRateReserve * 0.70)) }; zones["Zone 3 (Moderate) Karvonen"] = { lower: Math.round(restingHeartRate + (heartRateReserve * 0.70)), upper: Math.round(restingHeartRate + (heartRateReserve * 0.80)) }; zones["Zone 4 (Hard) Karvonen"] = { lower: Math.round(restingHeartRate + (heartRateReserve * 0.80)), upper: Math.round(restingHeartRate + (heartRateReserve * 0.90)) }; zones["Zone 5 (Maximum) Karvonen"] = { lower: Math.round(restingHeartRate + (heartRateReserve * 0.90)), upper: Math.round(restingHeartRate + (heartRateReserve * 1.00)) }; } var htmlOutput = "

Your Cycling Heart Rate Zones:

"; htmlOutput += "Estimated Maximum Heart Rate: " + maxHeartRate + " bpm"; if (restingHeartRate > 0) { htmlOutput += "Resting Heart Rate: " + restingHeartRate + " bpm"; } for (var zoneName in zones) { if (zones.hasOwnProperty(zoneName)) { var zone = zones[zoneName]; var unit = " bpm"; // Ensure lower bound doesn't exceed upper bound, and both are within realistic limits var lowerBound = Math.max(0, zone.lower); var upperBound = Math.min(maxHeartRate, zone.upper); if (lowerBound > upperBound) lowerBound = upperBound; htmlOutput += "

" + zoneName + ": " + lowerBound + unit + " – " + upperBound + unit + "

"; } } resultsDiv.innerHTML = htmlOutput; }

Understanding Cycling Heart Rate Zones

Heart rate training is a fundamental aspect of improving cycling performance, endurance, and recovery. By monitoring your heart rate, you can ensure you're training at the right intensity for your goals. Cycling heart rate zones are specific ranges of your maximum heart rate, each corresponding to different physiological benefits and training effects.

Why Train in Heart Rate Zones?

Optimized Training: Ensures you're working hard enough to stimulate adaptation but not so hard that you overtrain or risk injury.
Improved Endurance: Lower zones build aerobic base, crucial for long rides.
Enhanced Performance: Higher zones develop speed, power, and lactate threshold.
Better Recovery: Very light zones aid in active recovery and can improve blood flow to muscles.
Gauge Effort: Provides an objective measure of how hard you are working, regardless of external factors like terrain or wind.

Calculating Your Heart Rate Zones

The most common methods for calculating heart rate zones involve your maximum heart rate (MHR) and sometimes your resting heart rate (RHR).

1. Maximum Heart Rate (MHR):

Your MHR is the highest number of times your heart can beat per minute during intense physical activity. While the most accurate way to determine MHR is through a lab stress test, a common and simple formula is: MHR = 220 – Age. If you know your actual MHR from testing, use that for more precise zones.

2. Resting Heart Rate (RHR):

Your RHR is your heart rate when you are completely at rest, typically measured first thing in the morning before getting out of bed. You can find this by taking your pulse for 60 seconds. A lower RHR generally indicates better cardiovascular fitness.

The Two Main Methods for Zone Calculation:

A. Percentage of Maximum Heart Rate Method:

This is the most straightforward method. It divides your MHR into zones based on percentages.

Zone 1 (Very Light): 50-60% of MHR. For warm-ups, cool-downs, and active recovery.
Zone 2 (Light): 60-70% of MHR. Builds aerobic base and endurance.
Zone 3 (Moderate): 70-80% of MHR. Improves aerobic capacity and tempo.
Zone 4 (Hard): 80-90% of MHR. Increases lactate threshold and sustained power.
Zone 5 (Maximum): 90-100% of MHR. Develops peak power and VO2 max.

B. Karvonen Formula (Heart Rate Reserve Method):

This method is considered more accurate as it takes your RHR into account, providing a more personalized set of zones.

First, calculate your Heart Rate Reserve (HRR): HRR = MHR – RHR.

Then, apply percentages to the HRR and add your RHR back:

Target Heart Rate = (HRR * %Intensity) + RHR

Zone 1 (Very Light): 50-60% of HRR + RHR
Zone 2 (Light): 60-70% of HRR + RHR
Zone 3 (Moderate): 70-80% of HRR + RHR
Zone 4 (Hard): 80-90% of HRR + RHR
Zone 5 (Maximum): 90-100% of HRR + RHR

Example Calculation

Let's consider a cyclist who is 35 years old.

Age: 35
Estimated MHR: 220 – 35 = 185 bpm
Let's assume their Resting Heart Rate (RHR) is 58 bpm.

Using the Percentage of MHR Method:

Zone 1 (50-60%): 185 * 0.50 = 93 bpm to 185 * 0.60 = 111 bpm
Zone 2 (60-70%): 185 * 0.60 = 111 bpm to 185 * 0.70 = 130 bpm
Zone 3 (70-80%): 185 * 0.70 = 130 bpm to 185 * 0.80 = 148 bpm
Zone 4 (80-90%): 185 * 0.80 = 148 bpm to 185 * 0.90 = 167 bpm
Zone 5 (90-100%): 185 * 0.90 = 167 bpm to 185 * 1.00 = 185 bpm

Using the Karvonen Formula:

HRR: 185 (MHR) – 58 (RHR) = 127 bpm
Zone 1 (50-60%): (127 * 0.50) + 58 = 64 + 58 = 122 bpm to (127 * 0.60) + 58 = 76 + 58 = 134 bpm
Zone 2 (60-70%): (127 * 0.60) + 58 = 134 bpm to (127 * 0.70) + 58 = 89 + 58 = 147 bpm
Zone 3 (70-80%): (127 * 0.70) + 58 = 147 bpm to (127 * 0.80) + 58 = 102 + 58 = 160 bpm
Zone 4 (80-90%): (127 * 0.80) + 58 = 160 bpm to (127 * 0.90) + 58 = 114 + 58 = 172 bpm
Zone 5 (90-100%): (127 * 0.90) + 58 = 172 bpm to (127 * 1.00) + 58 = 127 + 58 = 185 bpm

As you can see, the Karvonen formula generally yields higher heart rate zones, especially in the lower intensities, when RHR is low, indicating a greater capacity for aerobic work.

Using this calculator can help you plan your cycling workouts effectively, whether you're aiming for a strong aerobic base, improved climbing power, or faster recovery.