What is the difference between stroke rate and distance per stroke

By John Hansen | Nov. 12, 2019, 1:35 p.m. (ET)

swimming stroke

When triathletes look at ways to improve their swimming performances, two elements often get overlooked — distance per stroke (DPS) and stroke rate (SR). Manipulating these two numbers can have a significant impact on a triathlete’s race and their stroke "efficiency," both in the pool and in open water.  In this article I will discuss what these terms mean, their importance to swimming performances, assessing your stroke and how to improve your weakness.

Terms

Distance Per Stroke (DPS): the distance traveled (in meters or yards) from each individual stroke.

Stroke Rate (SR): the number of strokes you take per minute (counting both left and right arm)

Importance

DPS: The first objectively measurable feature of good freestyle technique is Stroke Length - the distance a triathlete travels during each stroke cycle. A long stroke, that optimizes DPS, is critical to triathlon swimming performances because of its impact on efficiency and energy.

Efficiency: The greater distance you can travel per stroke cycle, the more efficient you are as a swimmer.

Energy: Energy conservation comes from the slower turnover or SR, reduced kick rate, and reduced drag often present in triathletes with a long DPS.

SR: A good metric for triathlete swimming performance is the rate at which he/she completes each stroke cycle.  An optimal SR is critical to swimming performances because of its impact on rhythm and inertia.

A higher stroke rate helps to maintain a positive swim rhythm, which means having a positive transfer of lower body energy to upper body power and appropriate rotation of your hips.

Swimming inertia means maintaining a constant speed while swimming and avoiding dead spots which affects speed and performance. This is especially critical in open water where you are dealing with a slower kick cadence, chop, sighting, the mental capacity to stay in the moment and other elements that will disrupt inertia.

DPS and SR are both important for good swimming performances. However, emphasizing one over another will result in poor performance. With regards to DPS, a long stroke can be less efficient because it introduces dead spots and there is no arm propulsion occurring at certain times during each stroke.

Conversely, an excessively high SR, relative to the propulsion being generated, reduces the efficiency you get from an effective DPS, increasing the degree of slippage in each stroke and producing more errors in stroke mechanics, creating drag.  It also negatively affects arm entry and your catch phase, reducing your pulling power. An effectively high SR, one that is producing a lot of propulsion and sustaining the athlete’s inertia, is more important in open water swimming where your SR may need to be 2-4 strokes per minute faster than your pool SR.

So, the answer to the question, “Which is best to improve your swimming, Stroke Rate vs Distance per Stroke?” the answer is both, but it depends ... a balance has to be made between the two, which begins by recognizing what type of stoke you have - a long DPS or High SR.

Stroke type:  DPS vs SR

DPS vs SR is typically an inverse relationship the faster you swim, so the goal for each triathlete is to find a balance between a good DPS and an optimal SR to swim the best possible times.

Let’s first consider how to determine which type of stroke you have by reviewing how to assess your DPS and SR.

To do these assessments, complete a 100-yard interval, at a moderate effort, in the middle of a long set when you are fatigued, and your true swim form is more apparent.

DPS – there are many ways to determine your DPS but the most accurate way is to count the number of strokes you take from the time you begin to stroke in the pool to the other side.  Most age group triathletes will begin their first stroke at 4 meters from the wall after a push-off so they stroke for a total of 21 meters.   If it takes you 22 strokes to complete that distance than your DPS is .95 meters (21/22=.95).

SR – Assessing SR is a little more difficult and requires a friend or coach with a stop watch.  During your 100-yard swim, have your friend/coach record the time it takes you to complete 10 strokes during each of the four lengths.  Take the average time and determine your SR.  For example, if your average time per 10 strokes is 8.75 seconds then your SR is as follows: (60 sec/8.75 sec) x 10=SR or 68.5/min

The next step is to determine what these results mean to you. Keep in mind each person will have their own optimal DPS and SR combination which is dependent on several factors.  However, there are ranges that will help to determine if you are an outlier and what metric you need to focus on for improved results.

Beginning with DPS, first determine how tall you are in meters since a good freestyle stroke distance should be within 55% to 70% of an athlete’s height.  Using the above DPS example if this swimmer is 5’9” or 1.75m we can determine if their stroke falls within the recommended range of 55-70% by performing the following math: DPS/Height or .95/1.75= 54.3%  This falls just under the low end of the recommended range.  So this swimmer should focus some attention to increasing their DPS, which will be discussed below.

With respect to SR, there are also ranges that will help you to determine if you are an outlier and if you need to refocus on improvement. To begin, once you have established your current SR, compare it to general norms for triathletes, which are dependent on your average pace per 100 during moderate effort swims, and are as follows:

Time/100yrds

1:50-2:00

1:40-1:50

1:30-1:40

1:20-1:30

1:10-1:20

1:00-1:10

:50-1:00

SR - Low

50

51

52

53

54

56

60

SR - High

62

64

65

70

80

90

100

If you fall outside the ranges, you should try to change your SR. If you fall outside the low end of the range, work to increase your SR, and if you fall outside the high end of the range, work to increase your DPS while trying to maintain your SR.

How to increase DPS

To help improve your DPS, engage in core strength training several times per week while using some tools, doing some traditional drills and completing specific swim sets which include the following: FINIS Tech TOC Audible Hip Rotation Tool – use the device in a variety of distances to enhance your hip rotation, the timing of your catch and the timing of your hand exit.

Finis Tempo Trainer – use the Finis Tempo Trainer in a variety of distances and sets to speed up and fine tune your SR.  Slowing down your SR will help you to enhance your efficiency while saving energy. For more details link to https://www.youtube.com/watch?v=Ihb4XP2Iet8

One arm swimming with fins: this drill teaches your body to rotate around the spine or long axis.

Sculling is a great drill to improve feel for the water, and your catch and pulling technique.

Swim Golf (SWOLF) – a great way to test our DPS abilities is known as swim golf, or swolf. The idea is to add together the time and the stroke count for a swim, trying to find the sweet spot where we’re best able to hold an efficient form at a high speed.

For example:

If you swim a 50 freestyle in 30 strokes and it takes 38 seconds, your swolf score would be 30 + 38 = 68. If you swam it again in 28 strokes, but it took 42 seconds, you’d have a higher (less desirable) swolf score of 70.

How to Increase Your Freestyle Stroke Rate

Finis Tempo Trainer – Speeding up your SR will help you to enhance your conditioning, timing, rhythm and inertia.  For more details link to https://www.youtube.com/watch?v=Ihb4XP2Iet8

Ankle Straps - Use a punctured tire tube and strap it around your ankles so it holds your ankles firm, not allowing for any kick. This will force you to enhance your SR just to complete the sets. It will also help you increase shoulder rotation power, encourage an early catch and improve the power in your catch.

A balance has to be made between DPS and SR to optimize your performances and that begins with assessments and ends with taking steps towards improvement.

John Hansen, USAT, and USA Swimming Level 1 Coach and USA Cycling Level 3 Certified coach, Folsom California. Hansen has an MS in Exercise Physiology and previously worked at the UC Davis Sports performance lab for five years. Hansen currently coaches the UC Davis Collegiate Club Triathlon team. Hansen also has his own coaching business, primarily coaching long course athletes, 70.3 and 140.6. Visit HansenMultisport.com or email john1hansen@sbcglobal.net.

The views expressed in this article are the opinion of the author and not necessarily the practices of USA Triathlon. Before starting any new diet or exercise program, you should check with your physician and/or coach.


Sources:  

1.SwimSmooth.com, Rhythm, Timing and Stroke Rate in Swimming, 2009

2.Mediterraswim.com, Metrics 101: Stroke Length, March, 2014

3.USA Masters Swimming, High Turnover vs The Right Turnover, Stuart McDougle, June 2015

4.Triathlete, What is the Ideal Stroke Rate, Gary Hall Sr August, 2015

5.USA Masters Swimming,  How to Find the Sweet Spot in Swimming Efficiency, Time Heggy, April 2017

6.FloSwimming, The Fine Line Between Distance Per Stroke & Stroke Rate Abbie Fish, April 2017

7.YourSwimBook.com, 3 Tips to Improve your distance per stroke, Oliver Poirier-Leroy, 2019