Sports and computer scientists of the University of Würzburg have taken a close look at current fitness trackers, activity sensors and training computers. They wanted to find out how accurate these devices are and whether they are suitable for athletes and everyday users to manage their training. A first study has been published recently.
Athletes modify their training every day. They do this to boost their performance and also to prevent injury. To be able to adjust the scope and the intensity of training, athletes need an overview of their performance data such as heart rate, maximum oxygen intake and other parameters. The data are recorded and stored by portable mini-computers or sensors, the so-called wearables.
These digital helpers are becoming increasingly popular in recreational sports, too: Recent surveys put the global market at around five and a half billion euros. “This is clearly the trend in the entire sports and leisure industry across all sports and applications,” says Professor Billy Sperlich and he adds: “But a lot of the devices have not been evaluated yet.”
The sports scientist leads the department of integrative and experimental training science at the University of Würzburg. For the current study, he and his colleague Peter Düking carefully scrutinized several products.
Estimation of energy expenditure inaccurate
The scientists did not perform a mere benchmark test as currently published in various runner's and sports magazines. Rather, they designed the study to determine what the individual devices are capable of and which of the measured parameters are important to manage training efficiently in the first place. "The devices available in the market today are already capable of measuring many biomarkers, but they are not entirely accurate," says Sperlich.
An example from recreational sports: Many people want to lose weight. Fitness trackers can help them get an overview of how many calories they use on one day. But: "Some devices have significantly underestimated the real energy expenditure when doing sports," Sperlich says.
With his team, Sperlich wants to compile as much data as possible to track down patterns. To assure data privacy and facilitate preparation and interpretation, Sperlich and Düking have teamed up with Andreas Hotho, Professor of Computer Science. "We hope that the huge volumes of data (keyword: big data) will enable us to determine the real effect of training on an individual more efficiently and to detect variables that we wouldn't have deemed relevant for performance before," Sperlich further.
Wrist-based heart rate monitors often lack accuracy
To manage the training in an optimal way, different sensors have to be combined. The gadgets examined by Sperlich, Düking and Hotho in a first step use different techniques: The classic chest strap provided good measuring accuracy, whereas the optical wrist-based monitoring of the heart rate is still in its infancy: "The measurement results of optical wrist sensors were frequently inaccurate, especially during intensive physical training," Sperlich says. This method uses LEDs that send light waves into the skin through tissue and blood vessels. The light is either absorbed, transmitted or reflected in this process. A lens located between the LEDs uses the reflected light, which is different depending on the levels of blood flow in each cardiac cycle, to derive the pulse.
Moreover, other sensors fitted into clothing or mattresses can provide information about an athlete's quality of sleep, measure the level of dehydration using skin sensors, monitor the core temperature with a kind of ear plug and determine the blood circulation in muscles, the maximum oxygen intake, and of course, the body weight.
Most commercially available devices are limited to duration, distance, speed and difference in altitude combined with heart rate and quality of sleep.
The next generation will be capable of much more
The electronic assistants of the next generation will also take other factors into account such as the runner's general well-being. "Unfortunately, the devices are not yet capable of sensing when somebody has an infection and should therefore train lightly in the morning," Sperlich names one example and adds: "But this will come, manufacturers are on the right track."
According to Sperlich, trainers and doctors do not have to feel that their existence is threatened by the smart gadgets and health monitors in the future. Some training computers are suitable when it comes to planning heart rate based training and achieving the set goals. Wearables also benefit people who find it more difficult to assess their physical capabilities, for example, having been injured or sick for some time.
Nevertheless, the two professions mentioned above will continue to be irreplaceable in everyday life. The scientist believes that it is reasonable and important to keep to personalized training schedules and to regularly consult your physician who has access to all health-related data. "Moreover, how we feel is the most sensitive stress marker we have," Sperlich says.
If you don't feel well, you should leave your running shoes in the wardrobe and stretch or get some rest instead.
"Comparison of non-invasive individual monitoring of the training and health of athletes with commercially available wearable technologies" by Peter Düking, Andreas Hotho, Franz K. Fuss, Hans-Christer Holmberg, and Billy Sperlich. Published in: Frontiers in physiology: http://journal.frontiersin.org/article/10.3389/fphys.2016.00071/abstract
Prof. Dr. Billy Sperlich, Phone: +49 931 31-81494, email@example.com
http://www.presse.uni-wuerzburg.de University's press contacts
Marco Bosch | Julius-Maximilians-Universität Würzburg
UT professor develops algorithm to improve online mapping of disaster areas
29.11.2016 | University of Tennessee at Knoxville
New standard helps optical trackers follow moving objects precisely
23.11.2016 | National Institute of Standards and Technology (NIST)
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy