Differentiated influence of off-road and on-road cycling practice on balance control and the related-neurosensory organization

The optimal method for improving postural balance in healthy young and older people: specific training for postural tasks encountered in personal physical practice

It is well known that regular exercise or physical activity (training) improves postural balance in healthy young and older subjects, but the optimal exercise or physical activity (i.e., likely to induce the greatest postural improvements) and the context in which it is carried out remain to be explored and determined for each population. The most beneficial adaptations would depend, in particular, on gestural conditions (body position, movement and gesture practiced) and material conditions (nature of the ground surface, sports equipment used, type of environment - stable or changing). In fact, the global postural adaptations induced by training do not result from the transfer between different trained and untrained postural tasks, but are the sum of the adaptations related to each trained postural task in healthy young and older subjects. Based on current knowledge, optimal training programs should include the full range of postural tasks encountered in personal physical practice for each population. To date, the method of implementing progressive postural balance tasks with different degrees of difficulty and instability has been used as the effective method to improve postural balance, but it should not be considered as the reference method. Instead, it should be considered as a complementary method to the one based on specific postural tasks. An intervention strategy is proposed for young and older adults consisting of three different steps (general, oriented and specific/ecologic training). However, some parameters still need to be explored and possibly reconsidered in future studies to improve postural balance in an optimal way.

One-Leg Stance Postural Sway Is Not Benefited by Bicycle Motocross Practice in Elite Riders

Balance has been positioned as an important performance skill in sport. Differences in postural control have been found between levels of expertise. However, this statement remains unanswered in some cyclic sports. This work aimed to describe the one-leg balance performance of a sample of elite BMX riders-racing and freestyle-compared to a control group formed by recreational athletes. The center of pressure (COP) of nineteen international BMX riders (freestyle, n = 7; racing, n = 12) and twenty physically active adults was analyzed in a 30-s one-leg stance test on both legs. COP dispersion and velocity variables were analyzed. Non-linear dynamics of postural sway were evaluated through Fuzzy Entropy and Detrended Fluctuation Analysis. BMX athletes did not show differences between legs in any of the variables. The control group did show differences between the dominant and non-dominant leg in the magnitude of variability of the COP in the mediolateral axis. Group comparison revealed non-significant differences. International BMX athletes did not show better balance parameters than the control group in a one-leg stance balance task. The adaptations derived from BMX practice do not have a significant impact in one-leg stance balance performance.

The ecological validity of traditional standing and novel bicycle balance and agility tests for predicting performance in mountain bikers

Falls are a common mechanism of injury in mountain biking and may be related to a loss of control of the bicycle. Traditionally, the components of bicycle control (balance and agility) are measured in standing and running, which may not reflect the skills required in mountain biking. In this paper, we present the validity of both traditional standing and novel bicycle-specific balance tests in mountain bikers. Twenty-nine male and female participants completed indoor laboratory tests and an outdoor downhill trail. Participants completed single-leg stance balance, Y-balance test, one static and four dynamic bicycle-specific balance tests, a bicycle agility test, and an outdoor downhill trail. Single-leg stance balance and Y-balance tests with eyes open had poor validity when associated with bicycle control. The static (r ​= ​-0.57, p = 0.001) and four dynamic bicycle balance tests (r ​= ​-0.51 to -0.78, p = 0.005 to 0.0001), and the bicycle agility test (r ​= ​0.87, p < 0.0001) had moderate to strong relationships with the outdoor downhill run. Single-leg stance balance and Y-balance tests with eyes open are not valid measures of performance on a mountain bike, and should not be used to assess these populations. Our novel bicycle balance tests have adequate validity to be used as measures of performance in mountain bikers.

Postural Balance in Young Tennis Players of Varied Competition Levels

The aim of this study was to investigate the effect of young tennis players' expertise on their postural balance (PB) under sensorial conditions with eyes open (EO) and with eyes closed (EC). Our participants were 75 healthy adolescents aged 15-18 years, divided into three groups based on their skill levels: (a) national tennis players (NAT; n = 25), regional tennis players (REG; n =25), and a control group of non-sport practitioners (CG; n = 25). We recorded center of pressure area and mean velocity on a force platform while participants stood in bipedal and unipedal stances in EO and EC conditions for all three groups. Statistical analyses showed that NAT participants swayed less than CG participants in all conditions and less than REG participants in the bipedal stance with EC and in the unipedal stance, both with EO and EC. Thus, tennis practice/experience may have improved PB in this sample, as high-level tennis players had better PB compared to novices, especially in challenging conditions.

Human Health and Outdoor Adventure Recreation: Perceived Health Outcomes

Forests and similar types of landscapes offer a myriad of outcomes and benefits often associated with participation in outdoor adventure recreation (OAR) activities. Previous research has shown that OAR participants are able to identify, perceive, and accurately report the effects and benefits of their participation. The health benefits of outdoor experiences, both active and more passive, have received a growing research interest, both as a setting and as a setting/activity complex. Research has identified six primary forms of health and well-being from outdoor and forest-type landscapes, including emotional, environmental, intellectual, social, spiritual, and physical. The preponderance of research in the health and wellness field synthesizes these forms into two primary categories, physical/physiological and mental/psychological. This study considered the health outcomes attributed to highly active OAR participation using three popular OAR activities: mountain biking (MTB), rock climbing (RC) and whitewater paddling (WW; including whitewater kayaking, whitewater canoeing, and whitewater rafting). A survey presented in situ to OAR participants in various areas of the Midwestern and Southeastern United States yielded 288 respondents. Using health perceptions and outcomes instruments as well as semi-structured interviews, the researchers found health to be an important factor for OAR participation. These findings are congruent with previous research that suggest that OAR participants specifically recreate in forested and other natural areas for enhanced physical and psychological health outcomes. The findings in this study also support the efficacy of the participation in OAR activities toward supporting both health improvement and maintenance. With physical and psychological health continuing to be an area of concern in today’s world, this study suggests that participation in OAR on forested and similar landscapes can be a successful health intervention strategy.

Does induced fatigue alter dynamic balance in athletes? A systematic review

OBJECTIVES

To determine the influence of induced fatigue on dynamic balance in healthy athletes.

DESIGN

Systematic review.

DATA SOURCES

PUBMED, MEDLINE, CINAHL, Sports Discus, and the Cochrane library from onset to May 28, 2019.

ELIGIBILITY CRITERIA

Eligible studies included any study examining the effects of induced-fatigue on dynamic balance, as measured by the SEBT/YBT, in healthy athletic populations. Studies with a low risk of bias were considered scientifically admissible for a best evidence synthesis.

RESULTS

Fifteen studies with low risk of bias were included - seven investigated recreational athletes while eight focused on competitive athletes. In the recreational population, five of the studies found significant decrease in dynamic balance following the fatiguing intervention. However, the remaining two concluded with insignificant changes. As for the competitive population, three studies showed significant effects of induced fatigue on dynamic balance, while five showed no effects.

CONCLUSION

There are conflicting results regarding the effects of induced fatigue on dynamic balance. The majority of studies focused on competitive athletes found that fatigue did not alter their dynamic balance. Per contra, the majority of studies focused on recreational athletes concluded the opposite - fatigue did indeed affect dynamic balance.

Balance control during stance - A comparison between horseback riding athletes and non-athletes

Horseback riding requires the ability to adapt to changes in balance conditions, to maintain equilibrium on the horse and to prevent falls. Postural adaptation involves specific sensorimotor processes integrating visual information and somesthesic information. The objective of this study was to examine this multisensorial integration on postural control, especially the use of visual and plantar information in static (stable) and dynamic (unstable) postures, among a group of expert horse rider women (n = 10) and a group of non-athlete women (n = 12). Postural control was evaluated through the center of pressure measured with a force platform on stable and unstable supports, with the eyes open and the eyes closed, and with the presence of foam on the support or not. Results showed that expert horse rider women had a better postural stability with unstable support in the mediolateral axis compared to non-athletes. Moreover, on the anteroposterior axis, expert horse riders were less visual dependent and more stable in the presence of foam. Results suggested that horseback riding could help developing particular proprioceptive abilities on standing posture as well as better postural muscle tone during particular bipodal dynamic perturbations. These outcomes provide new insights into horseback riding assets and methodological clues to assess the impact of sport practice.

Postural control of Parkour athletes compared to recreationally active subjects under different sensory manipulations: A pilot study

In Parkour activity, the aim is to move from one place to another as quickly and efficiently as possible by running, climbing, swinging, vaulting, rolling, crawling and jumping on tiny obstacles … . Performing these actions places a great demand on the postural control system. The purpose of the present study was to investigate postural control of Parkour practitioners - called Traceurs - compared to recreationally active (RA) subjects in different postural conditions after manipulating the visual and/or proprioceptive sensory inputs. Ten Traceurs (mean experience 5.9 ± 0.9 years; >5 hours per week) and 10 RA subjects participated in this study. We measured the centre of pressure area (CoP_A) of the upright standing bipedal and unipedal postures in different postural conditions: on a firm and on a foam surfaces; on an oscillating surface in the sagittal plane and in the frontal plane in eyes open and eyes closed. To evaluate vision contribution, the Romberg index (RI) was calculated. Results showed that Traceurs presented a significant (P < .001) lower CoP_A values compared to RA subjects in eyes closed condition, suggesting that they were able to maintain a better balance control when vision is removed. Traceurs seems to be less dependent on visual cues (lower RI values) and proprioceptive inputs for maintaining balance than RA subjects. According to our study, Parkour training (experience for at least five years with a minimum of five hours per week) may improve postural abilities of young adult practitioners in specific postural conditions.

Daily Bicycling in Older Adults May be Effective to Reduce Fall Risks-A Case-Control Study

Older adults gain many health benefits from riding bicycles regularly. We aimed to explore whether older persons who ride bicycles regularly have better balance than controls. Balance control and voluntary stepping were assessed in 20 older adults aged 65-85 years who live in an agricultural community village and who ride bicycles regularly, and 30 age- and gender-matched nonbicycle riders (NBR). Self-reported function and fear of fall were also assessed. Bicycle riders (BR) showed significantly better balance, faster voluntary stepping, and better self-reported advanced lower-extremity function compared with NBR. The results might suggest that bicycling regularly preserves balance control and speed of voluntary stepping in older adults because bicycling might maintain specific balance coordination patterns. The results should be treated with caution as bicycle riders were older adults who selected an active lifestyle (i.e., bicycling as well as living in an agricultural village) that may bias the results.

Regularity of Center of Pressure Trajectories in Expert Gymnasts during Bipedal Closed-Eyes Quiet Standing

We compared postural control of expert gymnasts (G) to that of non-gymnasts (NG) during bipedal closed-eyes quiet standing using conventional and nonlinear dynamical measures of center of foot pressure (COP) trajectories. Earlier findings based on COP classical variables showed that gymnasts exhibited a better control of postural balance but only in demanding stances. We examined whether the effect of expertise in Gymnastic can be uncovered in less demanding stances, from the analysis of the dynamic patterns of COP trajectories. Three dependent variables were computed to describe the subject's postural behavior: the variability of COP displacements (A_CoP), the variability of the COP velocities (V_CoP) and the sample entropy of COP (SEn_CoP) to quantify COP regularity (i.e., predictability). Conventional analysis of COP trajectories showed that NG and G exhibited similar amount and control of postural sway, as indicated by similar A_CoP and V_CoP values observed in NG and G, respectively. These results suggest that the specialized balance training received by G may not transfer to less challenging balance conditions such as the bipedal eyes-closed stance condition used in the present experiment. Interestingly, nonlinear dynamical analysis of COP trajectories regarding COP regularity showed that G exhibited more irregular COP fluctuations relative to NG, as indicated by the higher SEn_CoP values observed for the G than for the NG. The present results showed that a finer-grained analysis of the dynamic patterns of the COP displacements is required to uncover an effect of gymnastic expertise on postural control in nondemanding postural stance. The present findings shed light on the surplus value in the nonlinear dynamical analysis of COP trajectories to gain further insight into the mechanisms involved in the control of bipedal posture.

Vertigo in downhill mountain biking and road cycling

Vertigo has been described after the practice of mountain bike. This study aimed to investigate the prevalence of vertigo following competitions or training sessions of downhill mountain biking (DMB) or road cycling (RC). One hundred and two DMB riders, 79 road cyclists and 73 control participants filled in a survey intended to evaluate the prevalence of vertigo in daily living activities and following competitions or training sessions. Vertigo causal factors (crashes, head trauma, fatigue, characteristics of the path/road ridden) were recorded. DMB riders and road cyclists did not report more vertigo during daily living activities than controls. But DMB riders older than 30 had more risk to report vertigo than age-matched road cyclists (OR: 5.06, 95% CI: 1.23-20.62). Road cyclists aged between 20 and 29 were 2.59-fold (95% CI: 1.06-6.27) more likely to report vertigo than controls. After competitions and training sessions, DMB riders were 2.33-fold (95% CI: 1.22-4.41) more likely to report vertigo than road cyclists. Vertigo causal factors were crash with head trauma in DMB riders and fatigue in road cyclists. Vertigo during daily living activities may be of concern for cyclists, particularly older DMB riders. The accumulation of impacts (crashes, vibrations) during the career of a DMB rider may generate micro-traumatisms of the central nervous system and/or peripheral vestibular structures, particularly the otolith organs. In RC, the pathophysiological mechanisms generating vertigo might be effort-related disturbance of homeostasis. To avoid injuries, DMB riders should be aware that vertigo may occur at the end of training sessions or competitions.

Effect of expertise in shooting and Taekwondo on bipedal and unipedal postural control isolated or concurrent with a reaction-time task

It was hypothesized that training in 'static balance' or 'dynamic balance' sports has differential effects on postural control and its attention demands during quiet standing. In order to test this hypothesis, two groups of female athletes practicing shooting, as a 'static balance' sport, and Taekwondo, as a 'dynamic balance' sport, and a control group of non-physically active females voluntarily participated in this study. Postural control was assessed during bipedal and unipedal stance with and without performing a Go/No-go reaction time task. Visual and/or support surface conditions were manipulated in bipedal and unipedal stances in order to modify postural difficulty. Mixed model analysis of variance was used to determine the effects of dual tasking on postural and cognitive performance. Similar pattern of results were found in bipedal and unipedal stances, with Taekwondo practitioners displaying larger sway, shooters displaying lower sway and non-athletes displaying sway characteristics intermediate to Taekwondo and shooting athletes. Larger effect was found in bipedal stance. Single to dual-task comparison of postural control showed no significant effect of mental task on sway velocity in shooters, indicating less cognitive effort invested in balance control during bipedal stance. We suggest that expertise in shooting has a more pronounced effect on decreased sway in static balance conditions. Furthermore, shooters invest less attention in postures that are more specific to their training, i.e. bipedal stance.

The age-related performance decline in ultraendurance mountain biking

The age-related changes in ultraendurance performance have been previously examined for running and triathlon but not mountain biking. The aims of this study were (i) to describe the performance trends and (ii) to analyze the age-related performance decline in ultraendurance mountain biking in a 120-km ultraendurance mountain bike race the "Swiss Bike Masters" from 1995 to 2009 in 9,325 male athletes. The mean (±SD) race time decreased from 590 ± 80 min to 529 ± 88 min for overall finishers and from 415 ± 8 min to 359 ± 16 min for the top 10 finishers, respectively. The mean (±SD) age of all finishers significantly (P < 0.001) increased from 31.6 ± 6.5 years to 37.9 ± 8.9 years, while the age of the top 10 remained stable at 30.0 ± 1.6 years. The race time of mountain bikers aged between 25 and 34 years was significantly (P < 0.01) faster compared with the race time of older age groups. The age-related decline in performance in endurance mountain bikers in the "Swiss Bike Masters" appears to start earlier compared with other ultraendurance sports.