Running on a treadmill is a great alternative to running outdoors, but it can pose a problem when you're doing interval work. Intervals are usually given in distances that are easy to figure out on an outdoor track. For instance, 220 yards is approximately half a lap on a standard track. But treadmills usually measure the distance you walk or run in miles. To keep track of your interval work on the treadmill, you'll have to convert yards into miles.
Multiply 220 yards by the conversion factor 0.00057 to determine how many miles it equals. In this case, 220 yards equals 0.125 miles, which is 1/8th of a mile. You can use this formula to convert any distance in yards to distance in miles.
Set the interval on your treadmill to increments of 0.125 miles if your settings allow you to do so.
Monitor your treadmill display to note when you've run or walked intervals of 0.125 miles.
Keep track mentally of the number of .125-mile intervals you do if you cannot adjust your treadmill to keep track of this for you.