Co-Operative Design of a Coach Dashboard for Training Monitoring and Feedback.

Athlete development depends on many factors that need to be balanced by the coach. The amount of data collected grows with the development of sensor technology. To make data-informed decisions for training prescription of their athletes, coaches could be supported by feedback through a coach dashboard. The aim of this paper is to describe the design of a coach dashboard based on scientific knowledge, user requirements, and (sensor) data to support decision making of coaches for athlete development in cyclic sports. The design process involved collaboration with coaches, embedded scientists, researchers, and IT professionals. A classic design thinking process was used to structure the research activities in five phases: empathise, define, ideate, prototype, and test phases. To understand the user requirements of coaches, a survey (n = 38), interviews (n = 8) and focus-group sessions (n = 4) were held. Design principles were adopted into mock-ups, prototypes, and the final coach dashboard. Designing a coach dashboard using the co-operative research design helped to gain deep insights into the specific user requirements of coaches in their daily training practice. Integrating these requirements, scientific knowledge, and functionalities in the final coach dashboard allows the coach to make data-informed decisions on training prescription and optimise athlete development.

Perceived Training of Junior Speed Skaters versus the Coach's Intention: Does a Mismatch Relate to Perceived Stress and Recovery?

The aim of this observational study was to examine the differences between training variables as intended by coaches and perceived by junior speed skaters and to explore how these relate to changes in stress and recovery. During a 4-week preparatory period, intended and perceived training intensity (RPE) and duration (min) were monitored for 2 coaches and their 23 speed skaters, respectively. The training load was calculated by multiplying RPE by duration. Changes in perceived stress and recovery were measured using RESTQ-sport questionnaires before and after 4 weeks. Results included 438 intended training sessions and 378 executed sessions of 14 speed skaters. A moderately higher intended (52:37 h) versus perceived duration (45:16 h) was found, as skaters performed fewer training sessions than anticipated (four sessions). Perceived training load was lower than intended for speed skating sessions (-532 ± 545 AU) and strength sessions (-1276 ± 530 AU) due to lower RPE scores for skating (-0.6 ± 0.7) or shorter and fewer training sessions for strength (-04:13 ± 02:06 hh:mm). All training and RESTQ-sport parameters showed large inter-individual variations. Differences between intended-perceived training variables showed large positive correlations with changes in RESTQ-sport, i.e., for the subscale's success (r = 0.568), physical recovery (r = 0.575), self-regulation (r = 0.598), and personal accomplishment (r = 0.589). To conclude, speed skaters that approach or exceed the coach's intended training variables demonstrated an increased perception of success, physical recovery, self-regulation, and personal accomplishment.

How Do Runners Experience Personalization of Their Training Scheme: The Inspirun E-Coach?

Among runners, there is a high drop-out rate due to injuries and loss of motivation. These runners often lack personalized guidance and support. While there is much potential for sports apps to act as (e-)coaches to help these runners to avoid injuries, set goals, and maintain good intentions, most available running apps primarily focus on persuasive design features like monitoring, they offer few or no features that support personalized guidance (e.g., personalized training schemes). Therefore, we give a detailed description of the working mechanism of Inspirun e-Coach app and on how this app uses a personalized coaching approach with automatic adaptation of training schemes based on biofeedback and GPS-data. We also share insights into how end-users experience this working mechanism. The primary conclusion of this study is that the working mechanism (if provided with accurate data) automatically adapts training sessions to the runners' physical workload and stimulates runners' goal perception, motivation, and experienced personalization. With this mechanism, we attempted to make optimal use of the potential of wearable technology to support the large group of novice or less experienced runners and that by providing insight in our working mechanisms, it can be applied in other technologies, wearables, and types of sports.

Real-time feedback by wearables in running: Current approaches, challenges and suggestions for improvements.

Injuries and lack of motivation are common reasons for discontinuation of running. Real-time feedback from wearables can reduce discontinuation by reducing injury risk and improving performance and motivation. There are however several limitations and challenges with current real-time feedback approaches. We discuss these limitations and challenges and provide a framework to optimise real-time feedback for reducing injury risk and improving performance and motivation. We first discuss the reasons why individuals run and propose that feedback targeted to these reasons can improve motivation and compliance. Secondly, we review the association of running technique and running workload with injuries and performance and we elaborate how real-time feedback on running technique and workload can be applied to reduce injury risk and improve performance and motivation. We also review different feedback modalities and motor learning feedback strategies and their application to real-time feedback. Briefly, the most effective feedback modality and frequency differ between variables and individuals, but a combination of modalities and mixture of real-time and delayed feedback is most effective. Moreover, feedback promoting perceived competence, autonomy and an external focus can improve motivation, learning and performance. Although the focus is on wearables, the challenges and practical applications are also relevant for laboratory-based gait retraining.

The isometric torque at which knee-extensor muscle reoxygenation stops.

PURPOSE: We investigated the knee-extensor torque at which reoxygenation (inflow of arterial blood) during an isometric contraction stopped, whether this torque depended on maximal torque capacity (MTC), and whether there were differences among the synergists. METHODS: Isometric knee-extension torque was measured using a dynamometer with 90 degrees angles in the hip and knee. Maximal voluntary activation (established with superimposed nerve stimulation) was > 90% in the 15 healthy male subjects (20-30 yr). Near-infrared spectroscopy (NIRS) was used to measure changes in muscle oxygenation of the vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF) muscle during submaximal isometric contractions at intensities of 20-45% MTC with 5% increments, applied in randomized order and divided over 2 d. At each torque, a contraction with an inflated pressure cuff (450 mm Hg), inducing full arterial occlusion, was followed (10 min of rest) by a second contraction without the cuff. RESULTS: MTC ranged from 178 to 348 N.m. The torque at which maximal deoxygenation (all oxygen consumed) during contraction without the cuff became similar (P < 0.05) to the maximal deoxygenation reached with the cuff (indicative for complete occlusion of blood flow during the contraction without the cuff) was significantly higher for the RF (35% MTC) than for both vasti (25% MTC). There was no significant relation between MTC and relative (% MTC) torque at which muscle reoxygenation stopped. CONCLUSION: Knee-extensor reoxygenation stopped at lower torques than previously reported for blood flow in this muscle, and this occurred at the same % MTC in subjects of different strength but at different % MTC for the different synergists.