Measurement Accuracy of the HTC VIVE Tracker 3.0 Compared to Vicon System for Generating Valid Positional Feedback in Virtual Reality.

For realistic and reliable full-body visualization in virtual reality, the HTC VIVE Tracker could be an alternative to highly complex and cost- and effort-intensive motion capture systems such as Vicon. Due to its lighter weight and smaller dimensions, the latest generation of trackers is proving to be very promising for capturing human movements. The aim of this study was to investigate the accuracy of the HTC VIVE Tracker 3.0 compared to the gold-standard Vicon for different arrangements of the base stations and various velocities during an athletic movement. Therefore, the position data from three trackers attached to the hip, knee and ankle of one sporty participant were recorded while riding a bicycle ergometer at different pedaling frequencies and different base station arrangements. As parameters for the measurement accuracy, the trajectories of the linear motion of the knee and the circular motion of the ankle were compared between VIVE and Vicon by calculating the spatial distance from the raw data at each point in time. Both the pedaling frequency and the arrangement of the base stations significantly affected the measurement accuracy, with the lowest pedaling frequency of 80 rpm and the rectangular arrangement recommended by the manufacturer showing the smallest spatial differences of 10.4 mm ± 4.5 mm at the knee and 11.3 mm ± 5.1 mm at the ankle. As the pedaling frequency increased gradually (120 rpm and 160 rpm), the measurement accuracy of the trackers per step decreased less at the knee (approximately 5 mm) than at the ankle (approximately 10 mm). In conclusion, the measurement accuracy for various athletic skills was high enough to enable the visualization of body limbs or the entire body using inverse kinematics in VR on the one hand and, on the other hand, to provide initial insights into the quality of certain techniques at lower speeds in sports science research. However, the VIVE trackers are not suitable for exact biomechanical analyses.

[Influence of the dementia stage on motor skills in senior citizens]. / Einfluss des Demenzgrades auf die motorischen Fähigkeiten von Senioren.

BACKGROUND: The progressive course of dementia is not only manifested in the increasing impairment of cognitive functions but also in the motor skills of those affected and also impairs their mobility and independence in coping with everyday tasks. The present study investigated whether and to what extent there is a difference in selected skills of motor performance depending on the stages of dementia. MATERIAL AND METHODS: This study included 32 senior citizens with mild dementia (group A; 84.3 ± 6.1 years) and 27 senior citizens with moderate dementia (group B; 85.6 ± 5.5 years), whose classification was based on the mini-mental state examination (MMSE). The following motor tests were used: the hand dynamometer test (general strength), the drop bar test (motor reaction ability), frailty and injuries: cooperative studies of intervention techniques (FICSIT­4; balance), the timed up-and-go test (TUG) and the modified chair rising test (CRT; both assess mobility and transfer performances in everyday life). RESULTS: Group A, in contrast to group B, showed significantly better motor performance in all motor tests except the drop bar test. The largest differences were found in the CRT (p = 0.000) and TUG (p = 0.011). CONCLUSION: In terms of overall strength, balance and mobility, people with more advanced dementia showed lower performance. Therefore, subsequent studies investigating the impact of dementia on motor skills should always include a classification of dementia levels. Intervention programs should contain physical activities that focus on increasing general strength as well as balance.

Persisting inter-limb differences in patients following total hip arthroplasty four to five years after surgery? A preliminary cross-sectional study.

BACKGROUND: Total hip arthroplasty (THA) is an effective procedure for patients with end-stage hip osteoarthritis. However, whether or not pre-operatively existing functional deficits are persisting several years post-surgery in the affected limb has not been thoroughly researched. Therefore, the primary aim of this preliminary study was to include patients four to five years after undergoing THA and to investigate potential differences between the operated and non-operated leg in hip strength, range of motion (ROM), balance, and gait. The secondary aim was to compare these values from the operated leg of the patients to those of the legs of healthy subjects. METHODS: Sixteen patients (age: 65.20 ± 5.32 years) following unilateral THA (post-operation time: 4.7 ± 0.7 years) and ten, healthy, age-matched control subjects (age: 60.85 ± 7.57 years) were examined for maximum isometric hip muscle strength, active ROM of the hip joint, balance and gait on both limbs. Paired t-tests were used to assess the inter-limb differences in the THA group. Analyses of covariance (ANCOVA) were performed to compare groups, using age as a covariate. RESULTS: The analysis of inter-limb differences in patients following THA revealed significant deficits on the operated side for hip abduction strength (p = 0.02), for hip flexion ROM (p < 0.01) and for balance in terms of the length of center of pressure (COP) (p = 0.04). Compared to values of the control subjects, the patients demonstrated significantly reduced hip strength in flexion, extension and abduction (p < 0.05) on the operated leg as well as reduced ROM measures in hip flexion, extension and abduction (p < 0.05). CONCLUSIONS: The first results of this explorative study indicated that inter-limb differences as well as reduced hip strength and hip ROM compared with control subjects were still present four to five years after THA. These persisting asymmetries and deficits in patients following THA may be one explanation for the decrease in health-related quality of life (HRQoL) seen in patients over the years after surgery. Further studies are required to replicate these findings with a larger sample size. TRIAL REGISTRATION: DRKS, DRKS00016945. Registered 12 March 2019 - Retrospectively registered.

Analysis of anticipation by 3D motion capturing - a new method presented in karate kumite.

Anticipation is an important performance factor in karate kumite. A new approach analysing anticipation in realistic combat situations by motion capturing with a high temporal resolution is presented. The advantage of this approach is that both karate athletes interacting sports specific can be recorded synchronously; thus, the presented method has the potential to analyse visual information pickup due to coordination pattern of interaction between real athletes. The aim is to demonstrate the usability of the current method for anticipation research and to investigate if the distance between two athletes and their attacking technique play a role in the reaction of the defending athlete. Furthermore, relevant cues lying within each attacking technique and little individual differences are shown. Four male karate athletes took part in this study. Logistic regression indicated that both factors (distance × attacking technique) play a significant role in reaction. However, a correlation between these factors shows that only the attacking technique is a good predictor for reaction. Results show that the attacking technique jabbing punch (jap. Kizami-Zuki) was easier to anticipate than the attacking techniques reverse punch (jap. Gyaku-Zuki) and the round kick (jap. Mawashi-Geri).

Influence of Previous Failed Antispasticity Therapy on the Efficacy and Tolerability of THC:CBD Oromucosal Spray for Multiple Sclerosis Spasticity.

BACKGROUND: Sativex® (THC:CBD oromucosal spray) is indicated as add-on treatment for patients with moderate to severe multiple sclerosis (MS) spasticity. We aimed to determine whether antispasticity treatment history influenced the efficacy and safety of add-on THC:CBD oromucosal spray in MS spasticity patients. METHODS: Post hoc analysis of an enriched-design clinical trial of THC:CBD oromucosal spray versus placebo, using records of patients under previous and current ineffective antispasticity therapies. Subgroups were patients with at least 1 failed therapy attempt with either baclofen or tizanidine (Group 1) or at least 2 failed therapy attempts with both baclofen and tizanidine (Group 2). SUMMARY: Of 241 patients in the intent-to-treat population, 162 and 57 patients met the criteria for Groups 1 and 2, respectively. In all groups, response on the spasticity 0-10 Numerical Rating Scale was significantly greater with THC:CBD oromucosal spray versus placebo, for minimal clinically important difference (MCID ≥18% improvement vs. baseline) and clinically important difference (CID, ≥30% improvement vs. baseline). THC:CBD oromucosal spray improved spasticity-related symptoms such as sleep quality and timed 10-meter walk independent of the number of prior failed therapy attempts. Tolerability was not influenced by pre-treatment history. CONCLUSIONS: THC:CBD oromucosal spray provided consistent relief with good tolerability in MS spasticity patients irrespective of their antispasticity pre-treatment history.

Changes in dual-task performance after 5 months of karate and fitness training for older adults to enhance fall prevention.

BACKGROUND: Demographic changes resulting in an aging population are major factors for an increase of fall-related injuries. Especially in situations where dual tasks such as walking whilst talking have to be performed simultaneously the risk of a fall-related injury increases. It is well known that some types of martial art (e.g. Tai Chi) can reduce the risk of a fall. It is unknown if the same is true for karate. AIM AND METHODS: In this randomized, controlled study 68 people with a mean age of 69 years underwent 5-month karate training, 5-month fitness training or were part of a control group. Before and after the time of intervention a gait analysis with normal walk, a cognitive dual task and a motor dual task were performed. The gait parameter step frequency, walking speed, single-step time and single-step length were investigated. RESULTS: It could be seen that all groups improved their gait parameters after a 5-month period, even the control group. A sporty intervention seems to affect mainly the temporal gait parameters positively. This effect was especially demonstrated for normal walk and cognitive dual task. CONCLUSIONS: An improvement of the human walk seems to be possible through karate and fitness training, even under dual-task conditions. A prolonged intervention time with multiple repetitions of gait analysis could give better evidence if karate is a useful tool to increase fall prevention.

Changes in Selected Cognitive and Motor Skills as Well as the Quality of Life After a 24-Week Multidimensional Music-Based Exercise Program in People With Dementia.

The loss of independence is one of the greatest consequences of dementia. Multidimensional music-based exercise programs could counteract. The present study investigates the effects of such a program on people with dementia and bases on a 24-week intervention with three measurement time points. Sixty-nine people with dementia were randomly assigned to the intervention (n = 43) and control group (n = 26). The following outcome parameters were measured: leg strength, gait, grip strength, balance, reaction time, selected cognitive abilities, and quality of life. A mixed ANOVA with repeated measurement showed significant interaction effects between group and time. After 24-weeks in contrast to the control group the intervention group significantly improved in leg strength (P = .001), balance (P = .001), gait (P = .001), grip strength (right P = .002, left P = .011), reaction time (P = .003), global cognition (P = .039), verbal fluency (P = .002), attention (P = .013) and quality of life (P = .011). In conclusion, the program enhanced selected cognitive and motor skills and quality of life.

Relationship Between Self-Reported Function, Functional Tests and Biomechanical Parameters in Patients 12 Months After Total Hip Arthroplasty: A Preliminary Cross-Sectional Study.

Background/Purpose: Several methods are used to evaluate the outcome of total hip arthroplasty (THA), however, their relationship at different time points after surgery is unclear. The purpose of this exploratory study was to investigate correlations between self-report function, performance-based tests (PBTs) and biomechanical parameters in patients 12 months after THA. Methods: Eleven patients were included in this preliminary cross-sectional study. Hip disability and Osteoarthritis Outcome Score (HOOS) was completed for self-reported function. As PBTs, the Timed-up-and-Go test (TUG) and 30-Second-Chair-Stand test (30CST) were used. Biomechanical parameters were derived from analyses of hip strength, gait and balance. Potential correlations were calculated using Spearman correlation coefficient r. Results: HOOS scores and parameters of PBTs showed moderate to strong correlations (0.3 < r < 0.7). Correlation analysis between HOOS scores and biomechanical parameters revealed moderate to strong correlations for hip strength whereas correlations with gait parameters and balance were rather weak (r < 0.3). Moderate to strong correlations were also found between parameters of hip strength and 30CST. Conclusion: For THA outcome assessment 12 months after surgery, our first results indicate that self-report measures or PBTs could be used. Analysis of hip strength also appears to be reflected in HOOS and PBT parameters and may be considered as an adjunct. Given the weak correlations with gait and balance parameters, we suggest that gait analysis and balance testing should be performed in addition to PROMs and PBTs as they may provide supplementary information, especially for THA patients that are at risk for falls.

Gymnastic skills on a balance beam with simulated height.

Virtual reality (VR) is a valuable tool for simulating dangerous situations and training under these conditions with a reduced possibility of injury. This could be beneficial within different sports scenarios. In gymnastics, the height of the balance beam can be dangerous and frightening, especially for beginners. Here, a simulated height can reduce the participant's risk of injury and facilitate entry to balance beam gymnastics. However, the investigation of sports performance in a virtual environment is rare. Therefore, the current study aims to compare beginners' performance in balance beam tasks between the real world (RW) and VR. 34 sports students executed gymnastic balancing forward, backward and the extension of one leg to the front, the side and the back on a regular balance beam in the RW and on a balance beam with simulated height in VR (using a head-mounted display). We analyzed beginners' performance in both conditions (RW and VR) regarding different criteria for each balance beam task. Statistical analyses show significant differences in performance with better results in RW (p < .05). Especially the body tension and the upper body posture were superior in RW. One explanation can be the more difficult regulation of the balance in VR. For the tasks where the motion took part in a fixed position on the beam, the further performance aspects were similar for RW and VR. When the participants moved along the beam, further performance aspects, like the leg extension, were better in RW. In total, the participants executed the VR balance beam tasks with decreased danger of injury due to the simulated height of the balance beam, but their performance was slightly limited. We conclude that for the first contact with the height of a balance beam, VR is a suitable tool to reduce the danger of injury occurring from falling off the beam and facilitate entry to balance beam gymnastics.

Application of Inertial Sensors to Identify Performance-Relevant Parameters in Olympic Hammer Throw.

The aim of this study is to find essential performance-determining biomechanical parameters in hammer throw. There is no consensus in science on this, for many reasons. Among other things, there is the high complexity of the movement in conjunction with the differences in the physical conditions of the individual athletes. The purpose was to make complete body analyses of six experienced throwers (2 × male, 4 × female). METHODS: The kinematics were collected with the full body sensor suit (Moven suit from Xsens with 17 inertial measurement units (IMU)). We considered 37 literature-based parameters. By means of correlation analyses, with regard to throwing distance, and a principal component analysis (PCA), performance-relevant parameters could be found. RESULTS: The most promising results occurred in stance times and left hand speed. These findings suggest, in accordance with other studies, that these parameters have a relevant influence on the throwing distance. Comparing acceleration and angular velocity with the throwing distance also look relevant for performance. CONCLUSIONS: Further research with a focus on technique and bigger differences in the throwing distance are necessary to obtain clearer performance relevant parameters.

Influence of body visualization in VR during the execution of motoric tasks in different age groups.

Virtual reality (VR) has become a common tool and is often considered for sport-specific purposes. Despite the increased usage, the transfer of VR-adapted skills into the real-world (RW) has not yet been sufficiently studied, and it is still unknown how much of the own body must be visible to complete motoric tasks within VR. In addition, it should be clarified whether older adults also need to perceive their body within VR scenarios to the same extent as younger people extending the usability. Therefore, younger (18-30 years old) and elderly adults (55 years and older) were tested (n = 42) performing a balance-, grasping- and throwing task in VR (HMD based) accompanied with different body visualization types in VR and in the RW having the regular visual input of body's components. Comparing the performances between the age groups, the time for completion, the number of steps (balance task), the subjective estimation of difficulty, the number of errors, and a rating system revealing movements' quality were considered as examined parameters. A one-way ANOVA/Friedmann with repeated measurements with factor [body visualization] was conducted to test the influence of varying body visualizations during task completion. Comparisons between the conditions [RW, VR] were performed using the t-Tests/Wilcoxon tests, and to compare both age groups [young, old], t-Tests for independent samples/Mann-Whitney-U-Test were used. The analyses of the effect of body visualization on performances showed a significant loss in movement's quality when no body part was visualized (p < .05). This did not occur for the elderly adults, for which no influence of the body visualization on their performance could be proven. Comparing both age groups, the elderly adults performed significantly worse than the young age group in both conditions (p < .05). In VR, both groups showed longer times for completion, a higher rating of tasks' difficulty in the balance and throwing task, and less performance quality in the grasping task. Overall, the results suggest using VR for the elderly with caution to the task demands, and the visualization of the body seemed less crucial for generating task completion. In summary, the actual task demands in VR could be successfully performed by elderly adults, even once one has to reckon with losses within movement's quality. Although more different movements should be tested, basic elements are also realizable for elderly adults expanding possible areas of VR applications.

Musical feedback system Jymmin® leads to enhanced physical endurance in the elderly-A feasibility study.

Background and objectives: Active music-making in combination with physical exercise has evoked several positive effects in users of different age groups. These include enhanced mood, muscular effectivity, pain threshold, and decreased perceived exertion. The present study tested the applicability of this musical feedback system, called Jymmin ®, in combination with strength-endurance exercises in a population of healthy older adults. Research design and methods: Sixteen healthy, physically inactive older adults (5 males, 11 females) at the mean age of 70 years performed physical exercise in two conditions: A conventional work-out while listening passively music and a Jymmin ® work-out, where musical sounds were created with one's work-out movements. According to the hypothesis that strength-endurance is increased during musical feedback exercise, parameters relating to strength-endurance were assessed, including exercise duration, number of repetitions, perceived exertion (RPE), and participants' mental state (Multidimensional Mood State Questionnaire; MDMQ). Results: Results show that participants exercised significantly longer while doing Jymmin ® (Mdn = 248.75 s) as compared to the conventional work-out (Mdn = 182.73 s), (Z = 3.408, p = 0.001). The RPE did not differ between conventional work-out and the Jymmin ® condition, even though participants worked out significantly longer during the Jymmin ® condition (Mdn = 14.50; Z = -0.905; p = 0.366). The results of the MDMQ showed no significant differences between both conditions (Z = -1.037; p = 0.300). Discussion and implications: Results show that participants could work out longer while showing the same perceived exertion, relating to increased physical endurance. Music feedback work-out encouraged a greater degree of isometric contractions (muscle actively held at fixed length) and, therefore, less repetitions in this condition. In addition to the previously described effect on muscle effectivity, this non-stereotypic contraction pattern during music feedback training may have enhanced endurance in participants supporting them to better proportion energetic reserves during training (pacing). Clinical trial registration: Identifier: DRKS00023645.

Corrigendum: Musical feedback system Jymmin® leads to enhanced physical endurance in the elderly-A feasibility study.

[This corrects the article DOI: 10.3389/fspor.2022.915926.].

Tunable Pseudo-Piezoelectric Effect in Doped Calcium Titanate for Bone Tissue Engineering.

CaTiO3 is a promising candidate as a pseudo-piezoelectric scaffold material for bone implantation. In this study, pure and magnesium/iron doped CaTiO3 are synthesized by sol-gel method and spark plasma sintering. Energy dispersive X-ray mapping confirm the homogenous distribution of doping elements in sintered samples. High-energy X-ray diffraction investigations reveal that doping of nanostructured CaTiO3 increased the strain and defects in the structure of CaTiO3 compared to the pure one. This led to a stronger pseudo-piezoelectric effect in the doped samples. The charge produced in magnesium doped CaTiO3 due to the direct piezoelectric effect is (2.9 ± 0.1) pC which was larger than the one produced in pure CaTiO3 (2.1 ± 0.3) pC, whereas the maximum charge was generated by iron doped CaTiO3 with (3.6 ± 0.2) pC. Therefore, the pseudo-piezoelectric behavior can be tuned by doping. This tuning of pseudo-piezoelectric response provides the possibility to systematically study the bone response using different piezoelectric strengths and possibly adjust for bone tissue engineering.

Effects of body visualization on performance in head-mounted display virtual reality.

Although there are many virtual reality (VR) applications in sports, only a handful of studies visualized the whole body. There is still a lack of understanding, how much of the own body must be visualized in the head-mounted display (HMD) based VR, to ensure fidelity and similar performance outcome as in the real-world. In the current study, 20 young and healthy participants completed three tasks in a real and virtual environment: balance task, grasping task, and throwing task with a ball. The aim was to find out the meaning of the visualization of different body parts for the quality of movement execution and to derive future guidelines for virtual body presentation. In addition, a comparison of human performance between reality and VR, with whole-body visualization was made. Focusing on the main goal of the current study, there were differences within the measured parameters due to the visualization of different body parts. In the balance task, the differences within the VR body visualization consisted mainly through no-body visualization (NB) compared to the other visualization types defined as whole-body (WB), WB except feet (NF), as well as WB except feet and legs (NLF). In the grasping task, the different body visualization seemed to have no impact on the participants' performances. In the throwing task, the whole-body visualization led to higher accuracy compared to the other visualization types. Regarding the comparison between the conditions, we found significant differences between reality and VR, which had a large effect on the parameters time for completion in the balance and grasping task, the number of foot strikes on the beam in the balance task, as well as the subjective estimation of the difficulty for all tasks. However, the number of errors and the quality of the performances did not differ significantly. The current study was the first study comparing sports-related tasks in VR and reality with further manipulations (occlusions of body parts) of the virtual body. For studies analyzing perception and sports performance or for VR sports interventions, we recommend the visualization of the whole body in real-time.

Revealing a masked Verwey transition in nanoparticles of coexisting Fe-oxide phases.

The attractive electronic and magnetic properties together with their biocompatibility make iron-oxide nanoparticles appear as functional materials. In Fe-oxide nanoparticle (IONP) ensembles, it is crucial to enhance their performance thanks to controlled size, shape, and stoichiometry ensembles. In light of this, we conduct a comprehensive investigation in an ensemble of ca. 28 nm cuboid-shaped IONPs in which all the analyses concur with the coexistence of magnetite/maghemite phases in their cores. Here, we are disclosing the Verwey transition by temperature dependent (4-210 K) Raman spectroscopy.

The influence of facial expressions on attack recognition and response behaviour in karate kumite.

Facial expressions play a crucial role in human daily life interactions, so it is possible that they contain relevant anticipatory cues. Therefore, we conducted two studies in karate kumite to analyse the influence of facial expressions on the attack recognition (study A) and on the response behaviour (study B). In study A, 10 karate athletes (age 14-26 years, national and international level) had to recognize temporally occluded karate attacks in 2 conditions (normal and blurred face of the attacker) and identify the upcoming attack (verbal reports). In study B, a natural fight was initiated with 12 karate athletes (age 15-32 years, national and international level) in 3 conditions: an attacker with a normal face, wearing a ski mask, and wearing a ski mask together with sunglasses. The measured parameters response quality and time for response were calculated applying the McNemar test (study A) and Friedman test (study B). Results of study A showed a significant improvement in the attack recognition in the blurred face condition compared to the normal face condition. In study B a significant improvement in time for response was observed in the ski mask and ski mask plus sunglasses conditions (r < 0.1). No significant difference for response quality was found in any of the three conditions. The results of our work indicate that the disguise of the attacker's face leads to a better attack recognition and response behaviour. We conclude that anticipatory cues in karate kumite context mainly lie in the attacker's movements and not in the attacker's face.

Examination of the reliability of an inertial sensor-based gait analysis system.

Gait analysis is an important and useful part of the daily therapeutic routine. InvestiGAIT, an inertial sensor-based system, was developed for using in different research projects with a changing number and position of sensors and because commercial systems do not capture the motion of the upper body. The current study is designed to evaluate the reliability of InvestiGAIT consisting of four off-the-shelf inertial sensors and in-house capturing and analysis software. Besides the determination of standard gait parameters, the motion of the upper body (pelvis and spine) can be investigated. Kinematic data of 25 healthy individuals (age: 25.6±3.3 years) were collected using a test-retest design with 1 week between measurement sessions. We calculated different parameters for absolute [e.g. limits of agreement (LoA)] and relative reliability [intraclass correlation coefficients (ICC)]. Our results show excellent ICC values for most of the gait parameters. Midswing height (MH), height difference (HD) of initial contact (IC) and terminal contact (TC) and stride length (SL) are the gait parameters, which did not exhibit acceptable values representing absolute reliability. Moreover, the parameters derived from the motion of the upper body (pelvis and spine) show excellent ICC values or high correlations. Our results indicate that InvestiGAIT is suitable for reliable measurement of almost all the considered gait parameters.

Comparing the effectiveness of karate and fitness training on cognitive functioning in older adults-A randomized controlled trial.

BACKGROUND: Recent studies demonstrate a slowdown in deterioration of cognitive functioning in old age through aerobic training. There is evidence that the combination of aerobic, balance, and coordination exercises leads to an improvement or maintenance of cognitive functions. Such age-related exercises can especially be found in East Asian martial arts. The purpose of the current study is to verify whether karate training for older adults improves cognitive functioning and, if an improvement can be found, which cognitive fields are influenced. METHODS: Eighty-nine older women and men (mean age: 70 years) participated in this study. The participants were randomized into 2 intervention groups (karate group and fitness group, duration of intervention: 5 months) and a control group. All participants had to accomplish a cognitive test battery before and after the intervention. In a secondary study the karate group had an additional intervention for another 5 months. RESULTS: The results show that there is a significant improvement in motor reactivity, stress tolerance, and divided attention only after the 5-month karate training period. Additionally, the results of the secondary study indicate further improvements after 10 months. CONCLUSION: The 5-month karate training can help to enhance attention, resilience, and motor reaction time, but a training period of 10 months is even more efficient.

Horse-rider interaction in dressage riding.

In dressage riding the pelvis of the rider interacts with the horse physically. However, there is little information about the influence of riding skill on the interaction of the human pelvis with the horse. Therefore this paper aims to study the interaction between horse and rider in professional riders (PRO) and beginners (BEG). Twenty riders rode in walk, trot, and canter in an indoor riding hall with inertial sensors attached to their pelvis and to the horses' trunk. Statistical analysis of waveform parameters, qualitative interpretation of angle-angle plots, and cross-correlation of horse and rider were applied to the data. Significant differences between PRO and BEG could be found for specific waveform parameters. Over all gaits PRO kept their pelvis closer to the mid-position and further forward whereas BEG tilted their pelvis further to the right and more backwards. The coupling intensity of horse and rider revealed differences between the gaits. Furthermore phase shifts were found between PRO and BEG. This paper describes a sensor-based approach for the investigation of interactions of the human pelvis with the trunk of a horse under in-field conditions. First the results show that the riding level influences the posture of a rider and secondly that differences can be detected with contemporary available sensor technology and methods.