Calculate your 100m/100y split and plan your training
Your Pace Per 100 Units
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Understanding Your Swimming Pace
In swimming, pace is typically expressed as the time it takes to swim 100 meters or 100 yards. Unlike running, where pace is usually measured per mile or kilometer, the "per 100" split is the standard metric used by coaches and competitive athletes to gauge aerobic efficiency and speed endurance.
Why Calculate Your Pace?
Interval Training: Set accurate "send-off" times for set repetitions (e.g., 10 x 100 on 1:45).
Race Planning: Determine your target splits for open water events or triathlons.
Progress Tracking: Monitor how your cardiovascular fitness improves over a season.
Practical Example
If you swim a 1,500m time trial in 25 minutes and 30 seconds, your pace is 1:42 per 100m. Knowing this number allows you to structure your workouts. To improve, you might perform sets at a "Threshold Pace," which is usually 2–3 seconds faster than your current 1,500m average.
function calculateSwimPace() {
var distance = document.getElementById("swimDistance").value;
var minutes = document.getElementById("swimMinutes").value;
var seconds = document.getElementById("swimSeconds").value;
var resultBox = document.getElementById("swimResultBox");
var paceOutput = document.getElementById("swimPaceOutput");
var paceDesc = document.getElementById("swimPaceDescription");
// Convert to numbers and handle empty inputs
distance = parseFloat(distance);
minutes = parseFloat(minutes) || 0;
seconds = parseFloat(seconds) || 0;
if (!distance || distance <= 0 || (minutes === 0 && seconds === 0)) {
alert("Please enter a valid distance and time.");
return;
}
// Total time in seconds
var totalSeconds = (minutes * 60) + seconds;
// Calculate seconds per 1 unit, then multiply by 100 for pace per 100
// Pace = (Total Time / Distance) * 100
var pacePer100TotalSeconds = (totalSeconds / distance) * 100;
// Convert back to MM:SS format
var paceMins = Math.floor(pacePer100TotalSeconds / 60);
var paceSecs = Math.round(pacePer100TotalSeconds % 60);
// Padding seconds with a leading zero if needed
var formattedSecs = paceSecs < 10 ? "0" + paceSecs : paceSecs;
// Display results
paceOutput.innerHTML = paceMins + ":" + formattedSecs;
paceDesc.innerHTML = "Based on swimming " + distance + " units in " + minutes + "m " + seconds + "s.";
resultBox.style.display = "block";
}