Affective States and Virtual Reality to Improve Gait Rehabilitation: A Preliminary Study.

Over seven million people suffer from an impairment in Mexico; 64.1% are gait-related, and 36.2% are children aged 0 to 14 years. Furthermore, many suffer from neurological disorders, which limits their verbal skills to provide accurate feedback. Robot-assisted gait therapy has shown significant benefits, but the users must make an active effort to accomplish muscular memory, which usually is only around 30% of the time. Moreover, during therapy, the patients' affective state is mostly unsatisfied, wide-awake, and powerless. This paper proposes a method for increasing the efficiency by combining affective data from an Emotiv Insight, an Oculus Go headset displaying an immersive interaction, and a feedback system. Our preliminary study had eight patients during therapy and eight students analyzing the footage using the self-assessment Manikin. It showed that it is possible to use an EEG headset and identify the affective state with a weighted average precision of 97.5%, recall of 87.9%, and F1-score of 92.3% in general. Furthermore, using a VR device could boost efficiency by 16% more. In conclusion, this method allows providing feedback to the therapist in real-time even if the patient is non-verbal and has a limited amount of facial and body expressions.

Time to Exhaustion at the Respiratory Compensation Point in Recreational Cyclists.

The time to exhaustion (tlim) at the respiratory compensation point (RCP) and whether a physiological steady state is observed at this workload remains unknown. Thus, this study analyzed tlim at the power output eliciting the RCP (tlim at RCP), the oxygen uptake (VO2) response to this effort, and the influence of endurance fitness. Sixty male recreational cyclists (peak oxygen uptake [VO2peak] 40-60 mL∙kg∙min-1) performed an incremental test to determine the RCP, VO2peak, and maximal aerobic power (MAP). They also performed constant-load tests to determine the tlim at RCP and tlim at MAP. Participants were divided based on their VO2peak into a low-performance group (LP, n = 30) and a high-performance group (HP, n = 30). The tlim at RCP averaged 20 min 32 s ± 5 min 42 s, with a high between-subject variability (coefficient of variation 28%) but with no differences between groups (p = 0.788, effect size = 0.06). No consistent relationships were found between the tlim at RCP and the different fitness markers analyzed (RCP, power output (PO) at RCP, VO2peak, MAP, or tlim at MAP; all p > 0.05). VO2 remained steady overall during the tlim test, although a VO2 slow component (i.e., an increase in VO2 >200 mL·min-1 from the third min to the end of the tests) was present in 33% and 40% of the participants in HP and LP, respectively. In summary, the PO at RCP could be maintained for about 20 min. However, there was a high between-subject variability in both the tlim and in the VO2 response to this effort that seemed to be independent of fitness level, which raises concerns on the suitability of this test for fitness assessment.

Impact of rider position and pedaling cadence on power output and bilateral asymmetry in indoor cycling.

BACKGROUND: This study examines the effects of pedaling cadence and the rider's position on power output and pedaling asymmetry during indoor cycling. METHODS: Participants were 25 male indoor cycling instructors (32.4±4.8 years; 75.7±4.9 kg; 174±4.2 cm) with at least 3 years of cycling experience. In a single session, participants completed 9 training intervals consisting of different combinations of position (standing, sitting), pedaling cadence (75, 100, 120 rpm) and training intensity (75, 80, 85% maximum heart rate, HRmax). RESULTS: During standing intervals, power output was lower (132.4±72.6 W vs. 197.5±53.5 W; P<0.05) and the bilateral leg asymmetry index was greater (52.2±76.6% vs. 12.4±9%; P<0.05) than when subjects pedaled while sitting for a similar work intensity. In contrast, higher power outputs (238.1±46.3 W vs. 153±52.7 W; P<0.05) and lower asymmetry indices (30.4±39.2% vs. 12.6±11%; P<0.05) were recorded in intervals performed at 75 rpm versus 120 rpm despite similar exercise intensities. CONCLUSIONS: Our findings indicate that at similar training intensities, pedaling while standing during indoor cycling generates fewer watts and greater asymmetry than pedaling while sitting. We also observed that a slower pedaling cadence (75 rpm) gives rise to greater generated power and a lower asymmetry index than a faster pedaling cadence (120 rpm).