Team USA Olympic swimmers had an advantage as soon as they hit the pool in Rio this summer thanks to a “motion tracking system” developed by BMW and engineered for USA Swimming. Used in training, the system was particularly useful in improving a swimmer’s kick.
First developed prior to the 2012 Olympic games, the system utilizes LED lights to sense and record a swimmer’s motion. The self-illuminating lights were affixed onto the swimmer’s shoulders, hips, knees, ankles and toes using 3D-printed mounts, which were designed to not hinder the athlete’s movement.
Peter Falt, Director at BMW Group Designworks and Russell Mark, National Team High Performance Consultant at USA Swimming were kind enough to shed some light on the details behind the combination of engineering and sport that was at play here.
When the BMW collaboration was presented, what were the elements you most wanted help with?
Russell Mark: Over the course of the last few decades, a lot has changed when it comes to swimsuits and gear, but there has been little advancement in the way swimmers analyze their strokes and kicks. It was great having a partner like BMW come on board with a commitment to finding ways to collaborate with our team and apply their expertise in engineering to address some of the real needs we’ve had – in this case it was the dolphin kick. We’ve known that the kick itself can be incredibly valuable, but until now there hasn’t been a good way to measure it to maximize the movement. The tool is helping us identify the ingredients that make up a successful dolphin kick by receiving instant feedback that can be applied the very next time they jump in the pool, allowing for a more customized coaching approach.
How did you use the tech in 2012?
RM: The tech in 2012 can be looked at as a first generation version of the current version that we have now. This current iteration is much more refined in the video capture with much more robust and detailed data analysis. The 2012 tech gave us some really good preliminary information that helped us get to where we are now. We were able to see the dolphin kick mechanics from this enhanced perspective for the first time ever, and just like any first-look would, we were able to learn from it and understand what we need to be focusing on.
How has it evolved since then?
RM: With LED’s to mark the critical joints and an entirely new analysis tool, the video capture process is much more reliable, let alone cooler to look at since the swimmer’s body is literally lit up. We are able to extrapolate the direction of the kick by tracking the orientation of the spine, and are able to see the variation of all of the joint angles relative to each other in order to gain understanding of the optimal combination of body movement. The dolphin kick is a natural motion to fish, and more natural to some swimmers than others, so we are constantly trying to optimize the technique for speed with various information.
What is an example of something you learned about your swimmers based on the tech?
RM: We’ve already seen some tangible results and improvements – for example, the first time swimmers can now be objectively compared to each other as another means of finding improvement learned by comparison to top performers. Our hope is that we can continue to fine tune this tool to assess our swimmers and improve it for the next generation.
The tech measures six points on the body, why are these the most important?
RM: The dolphin kick is essentially your body moving in a wave-type action (think of the “worm” dance move). The movement of each body segment needs to be synchronized to generate speed in the water. This movement can be optimized with just the right angles of each joint and timed correctly. The six points on the body correspond to the ends of the different segments that are in motion.
No two swimmers are alike, so this technology aims to help them learn what movements work best for their bodies to move faster in the water. In swimming, we tend to watch how the fastest swimmers move and try to emulate their technique. But if you don’t have the same body characteristics, the technique won’t work the same. In addition to the motion tracking system using LED lights to track those six points on the swimmer’s body – wrists, shoulders, hips, knees, ankles and toes – it also measures kick depth and rate.
Is this something you use during the Games or more of a training tool to adjust movements before competitions?
RM: Especially while this type of information is new to athletes and coaches, the tool will be used in training and our long-term preparation for competition. It will give athletes and coaches a baseline for what their technique is and then can be used for status checks if the necessary changes are being made. Similar to how we currently implement technique changes, as we get closer to our important competitions like the Olympics, hopefully all of the major changes have been made already and we’re just reinforcing the changes at that point.
We’ve been using the motion tracking system at the Olympic Training Center in Colorado Springs, but one of the latest upgrades is that it’s now portable so as we continue with its improvement process we hope to eventually bring the tool on the road with us.
SportTechie: What equipment do the swimmers have to wear in order to track and analyze form, and what goes into that equipment in order to do so?
Peter Falt: The tool is powered by the same combination of computer vision and software algorithms that are at the core of automated driving systems in BMW vehicles, so the motion tracking system uses LED lights to track six points on the swimmer’s body – wrists, shoulders, hips, knees, ankles and toes – as well as kick depth and rate. With the aggregated data, coaches can pinpoint the performance attributes of specific parts of the body and see how well all parts are working together to increase speed
Existing training techniques involve manually counting strokes and kicks from the deck, relying on the coach’s eye to help adjust alignment or making assumptions from underwater video footage. While using underwater cameras is not new to the sport, BMW’s technology is the first to provide quantitative data analysis of a swimmer’s movements in the water.
ST: What improvements have been made to the system since its initial creation in 2012?
PF: Initially developed in advance of the London Games, the exploratory tool has since undergone several evaluations and improvements in hopes of continuing to produce insights never before possible. Through an evolution process over the last few years, we’ve made improvements to both the hardware and software as they work in concert. For example, we now created two means of collecting and interpreting specific joint locations by the software, we call them headlights and taillights. Previously, we illuminated tattoos, whereas now we are also using self-illuminated LEDs for tracking.
The “headlight” approach uses LEDs like in BMW cars to illuminate a specific spectrum or colored tattoo that is placed on the swimmer in the needed joint locations. The “taillight” solution reversed this and used LEDs as illuminated markers that are place in the same specific locations. 3D printing was employed to house the LED “taillights” to create a mounting system that could not only hold up to the intense forces of Olympic swimmers, but also “disappear”, meaning that they are not noticeable by the swimmer or impede their motion in any way. This was important to ensure the training didn’t create a different feeling or result than would be experienced in real competition. This is also why we ruled out body suits or more obvious potential solutions that would have been a lot easier.
ST: What has the feedback been like from swimmers and coaches, particularly Olympians, and what role has that feedback played in developing the technology?
PF: At this stage, what we’ve heard from athletes and coaches is that they’re looking for marginal improvements, especially knowing that a .01 second advantage can mean the difference between winning a medal and going home empty handed. We consider this a collaborative partnership so the direct feedback from the athletes and coaches is what we’ll continue to lean on for improvements.
ST: What are the most significant changes swimmers and coaches have made in their training routines as a result of this technology?
PF: We’ve heard from a few swimmers that they have seen degrees of difference in several areas such as spine line, or the movement in their upper chest as compared to competitors.
ST: Going forward, how do you think this technology will change the sport of swimming?
PF: Technology like this can significantly help a swimmer’s training and times. The goal of BMW’s motion tracking tool is to help unleash the power of the dolphin kick at starts and turns, which can be a huge competitive advantage for a swimmers like Nathan Adrian and Maya DiRado. The tool has been an exploratory project that we’ll continue evaluating over time, but our hope is that the potential of its outcome can make a significant impact on the future generation of swimmers.
ST: How can the technology be improved in the future?
PF: The motion tracking system was intentionally designed as a modular system for ongoing evolution and improvement. By comparing measurements to performance over time, coaches can continue to use BMW’s motion tracking tool to hone in on technique adjustments that work best for each individual swimmer.
ST: What is the most exciting innovation this technology has led to that you’re looking forward to seeing in action in Rio?
PF: The athletes told us that in this sport, if you can understand how to make yourself more efficient without expending more energy, that’s free money. If we can help with that in Rio, as well as with the next generation of swimmers to come, we’ll consider it a success.