Low Tech Lap Counting

23,034

13

5

Introduction: Low Tech Lap Counting

I swim for exercise but hate keeping track of how many laps I've completed. I searched for a lap counting solution and found waterproof sports watches and dedicated counters at \$30 and up. Those were overkill for what I needed, so I developed my own counting system that works great and costs pennies. Now I can spend my swim time thinking or unwinding instead of counting.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: What You Will Need

What you need:
- 4 rubber bands that fit comfortably around your wrist. You can even hijack the kids' sillybandz for this.

Step 2: Connect the Bands

Loop one band around another and back through itself so that they interlock and form a figure eight. Do the same for the second pair. Nothing tricky here, you are just making two standard rubber band chains with two bands each.

Step 3: Put the Bands On

Put one of the bands around your wrist with the knot towards the inside and so that its attached band hangs free. Do the same for the other wrist. This is the zero position from which you will start the count.

Step 4: Get Aquainted With the Counting System

Here's how it works...one hand counts by ones and the other hand counts by fives using rubber bands resting in the "slots" between your fingers and/or thumb to keep track of laps you have swum. You may recognize this as similar to the 4-sticks-and-a-slash tally system commonly used to count things, unless you are the studious type who will recognize it as base 5.

I use my left hand for the ones, my right hand for the fives and start at my thumbs as shown in the sketch. It really isn't important which hands/starting points you use as long as you can remember it and be comfortable with it. Though this system is quite simple, I recommend trying it out on dry land first so as not to distract the lifeguards.

Step 5: Begin Counting

After you complete your first lap, take the dangling band on your left wrist and loop it around your left thumb. (Front and back views shown below.) After the second, third and fourth laps, increment the count by moving the rubber band over by one finger (each further away from the thumb). After 4 laps the rubber band will between your pinkie and ring finger.

Step 6: Countinue Counting

After the 5th lap, return the band on your left hand to the starting position (dangling) and place the dangling band on your right wrist around your right thumb.

Continue after each additional lap moving the band on your left hand away from the thumb one slot at a time until you run out of slots, (indicating a multiple of 5 has been reached). Return the left hand band to the starting position and move the right hand band over one finger. Continue in the same manner until you reach 25 laps, then start over.

As shown in the photo below, I find it easiest to place one hand on the wall and move the band with the other hand.

Step 7: Where Am I?

To tell how many laps you've completed, count by fives on your right hand until you reach the band and add the remaining laps shown on your left hand. (If you've gone around more than once, add any multiples of 25 you have completed.)

Hey, I've done a kilometer already (22 laps x 50 yards per lap)!

Recommendations

115 8.7K
7 2.0K
304 17K
Concrete Class

18,744 Enrolled

5 Discussions

Brilliant! I love it! Got a smartwatch but it was too distracting. This works way better and my mind focus on the swim versus having to look and click buttons on the watch. I use hair bands instead of regular rubber bands so they won't pinch my skin. Thank you so much for sharing!!!

This is genius and so simple (and cheap!!) to do. I used it today for the first time and really was able to relax into my swim and not have to be always thinking, "This is 6...6...6..6....This is 7...7...7...7.." and still losing count. It did not take long to get into the swing of moving the bands every lap. Thank you!

GREAT IDEA ! This was so well done. What a wonderful instructable.

Very good thinking. It should be noted that this idea can easily be adapted to use the binary system, which would allow you to count up to 31 on one hand, and 1023 on two.