Diagnostics national coach Alexander Törpel (m.) works with fellow coaches Norbert Warnatzsch (l.) and Bernd Berkhahn (r.) at the Magdeburg federal base in Magdeburg.

Digitization is also inevitable in the sport of swimming. In the field of sports science, it is now advancing particularly quickly in Germany since Dr. Alexander Törpel was appointed national coach for diagnostics of the German Swimming Federation (DSV) in the fall of 2019. Thanks to him, DSV squads now train with optical sensors on goggles or swimming caps to track pulse levels live. Smart paddles to measure arm pull and digital platforms are also becoming more common. The intelligent use of digital possibilities is intended to support coaches and athletes in the training process so that, based on the more comprehensive knowledge, training can be designed as effectively as possible to ultimately swim faster.


In alignment with this goal, the German Swimming Federation (DSV) using new software for endurance performance diagnostics. “With INSCYD, everyone can immediately identify the physiological metrics that will most effectively improve athletes performance,” says Sebastian Weber, founder and one of the developers of the INSCYD software.


INSCYD is the new science partner of the German Swimming Federation e.V. (DSV). With the software, the physiological performance of a person can be represented in a detailed manner in order to make precise prescriptions for training and predictions for races. For this purpose, Weber has used basic physiological research and countless tests of athletes to validate the algorithms that makes these analyses possible.

2x World Champion 1500 m Freestyle swimmer Florian Wellbrock using Cortex

Data fills the gap between seeing and feeling

Based on only a few measured values, the software creates a 360° physiological performance profile of the energy metabolism of an athlete. The required data to run such an analysis consists of: A) basic measurements such as height, weight and gender, as well as parameters of body composition and – if available – exercise economy (determined by measuring oxygen uptake at different exercise levels), and B) data such as lactate values and swimming speed measured at different swimming distances. Key metrics which determine the performance of a swimmer such as the maximum oxygen uptake (VO2max) and the maximum lactate formation rate (VLamax) as markers for the aerobic and anaerobic metabolism – are precisely calculated. The realistic modeling of the energy metabolism as a function of swimming speed also provides precious insights into the rate of lactate accumulation at high intensities and the rate of recovery at lower intensities.

INSCYD data fills the knowledge gap between what a trainer sees and what an athlete feels, and does so better and faster than previously used testing methods – with much less testing effort. For example, before and after training cycles or individual training measures (e.g. an altitude training camp), new data sets can now be quickly determined with a simple performance test embedded into the regular training in order to accurately pinpoint the effect achieved by a certain training regime.

“Training stimuli should be modeled on the drawing board, so to speak, for upcoming exercise sessions. This can lead to a new era of sports science support.”

INSCYD enables the coach to create precise training prescriptions in a short term. In addition, one can run projections to make informed decisions how to proceed in training. “From a theoretical point of view, much more is possible through simulation calculations when creating a training program. This is currently a topic in science and practice that was also worked on two to three decades ago, but is now really coming into application due to technological advances and easier access to working on complex processes. This can lead to a new era of sports science support for the training process,” says Törpel.


Tactical advice for the race is also conceivable – if you know exactly how long you can maintain a certain speed, the ideal time for the final sprint can be determined more precisely. And for open water, an individual fueling strategy can be created to ensure enough carbohydrates are taken in during the race.

Great successes in Cycling and Triathlon

Scientist Törpel and the DSV national coaches have been following INSCYD and its success in the endurance scene for some time. They were ultimately convinced by how close the calculations came to their original measured values. “You just have to try it if you want to benefit from it,” explains Törpel. “With INSCYD, we would like to support coaches and athletes even better in the future with regard to endurance performance diagnostics as well as understanding the significant part of energy metabolism in swimming. The complex physiology of the energy metabolism will be analyzed in detail and training stimuli will be modeled on the drawing board for upcoming training sessions. We can now quantify the effect of the training and plan the next stimulus much more specifically. It’s comparable to motorsports: If I can precisely quantify the weight, displacement and horsepower of a car, I can calculate who’s faster down the home stretch.”

In other sports such as professional cycling, INSCYD can already boast amazing successes, e.g. Worlds number one ranked team in 2020 Jumbo-Visma from the Netherlands. In addition, the coaches of the professional Ironman athletes Sebastian Kienle and Lionel Sanders have been among the long-standing partners. Of course, the results from cycling and triathlon cannot simply and directly be transferred to the water. That’s why it’s now a matter of gathering experience and jointly developing program extensions for swimming.


"In swimming, what was previously assumed based on experiential knowledge can now be clarified with numbers." Törpel

The DSV then plans to integrate the system into the education and training of the coaching staff. “Understanding how training stimuli is created by the the design of resting periods, intensity and load time can be best developed and showcased with INSCYD data,” Törpel says. “What was previously assumed based on experiential knowledge can now be clarified with numbers.”