Mortality in Different Mountain Sports Activities Primarily Practiced in the Winter Season-A Narrative Review

Annually, millions of people engage in mountain sports activities all over the world. These activities are associated with health benefits, but concurrently with a risk for injury and death. Knowledge on death rates is considered important for the categorization of high-risk sports in literature and for the development of effective preventive measures. The death risk has been reported to vary across different mountain sports primarily practiced in the summer season. To complete the spectrum, the aim of the present review is to compare mortality rates across different mountain sports activities primarily practiced in winter. A comprehensive literature search was performed on the death risk (mortality) during such activities, i.e., alpine (downhill) skiing, snowboarding, cross-country skiing, ski touring, and sledging. With the exception of ski touring (4.4 deaths per 1 million exposure days), the mortality risk was low across different winter sports, with small activity-specific variation (0.3–0.8 deaths per 1 million exposure days). Traumatic (e.g., falls) and non-traumatic (e.g., cardiac death) incidents and avalanche burial in ski tourers were the predominant causes of death. Preventive measures include the improvement of sport-specific skills and fitness, the use of protective gear, well-targeted and intensive training programs concerning avalanche hazards, and sports-medical counseling for elderly and those with pre-existing diseases.

Effectiveness of a Mini-Trampoline Training Program on Balance and Functional Mobility, Gait Performance, Strength, Fear of Falling and Bone Mineral Density in Older Women with Osteopenia

Purpose

To evaluate the effectiveness of a combined balance-, strength-, and jumping-exercise intervention on a mini-trampoline performed by older women with osteopenia on static balance and functional mobility, gait speed, strength of the upper and lower limbs, fear of falling, as well as to investigate its influence on bone mineral density (BMD).

Patient and methods

Using a randomized controlled study design, participants (range: 56-83 years) were assigned either to the intervention group (IG; n=20, mean age 69.6 ± 5.3 years) performing a specifically tailored intervention on a mini-trampoline or to the control group (CG; n=20, 67.4 ± 6.8 years), that did not undertake any intervention beyond regular osteopenia treatment. The intervention was performed twice a week for 12 weeks, each session lasting 45-60 mins and consisted of balance, strength and jumping exercises. Static balance and functional mobility was measured by one-leg stance (OLS) and timed up and go test (TUG). Upper and lower limb strength was evaluated by the arm curl test (ACT) and the 30-s chair stand test (CST) whereas gait speed was measured by the 6 m walking test (WT). Fear of falling was measured using the Falls Efficacy Scale - International (FES-I). BMD was measured at the lumbar spine and femoral neck using Dual-energy X-ray absorptiometry (DXA).

Results

Significant interactions (group x time) were found for all parameters (p<0.001) except for BMD, measured at the lumbar spine (p=0.064) and femoral neck (p=0.073). All test parameters of balance and functional mobility tests (OLS, TUG), strength tests (ACT, CST), WT, FES-I and BMD (femoral neck) showed significant improvement in the IG (p<0.05).

Conclusion

The combined 12-week intervention was highly effective in improving balance and functional mobility, strength, gait performance and fear of falling in patients with osteopenia.

Effects of a heat and moisture exchanger on respiratory function and symptoms post-cold air exercise

PURPOSE

Exercise at temperatures below -15°C induces drying and cooling of lung airways which causes exercise-induced bronchoconstriction (EIB) and respiratory symptoms, especially in winter sport athletes. The objective of this study was to evaluate whether a heat and moisture exchanger (HME) worn during intense cold air exercise improves lung function and reduces respiratory symptoms in healthy winter sport athletes.

METHODS

Seven active males and six active females (maximum oxygen uptake 61.9 ± 6.9 and 52.2 ± 5.3 mL/kg/min), all active or former winter sport athletes, completed running trials with and without HME in random order on 2 days in an environmental chamber (-20°C temperature, humidity 46.2%). Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV₁ ), forced expiratory flow at 25%-75% (FEF_25%-75% ), and FEF at 50% (FEF_50% ) were measured pre- and post-exercise (3, 6, 10, 15, and 20 minutes). Respiratory symptoms were reported after exercise.

RESULTS

Significant interaction effects were observed for FEV₁ and FEF_25%-75% . Mean decrease of FVC (-5.9%, P ≤ .001) and FEV₁ (-4.2%, P = .003) was largest 3 minutes post-exercise without HME. There was an increase of FEV₁ , FEF_25%-75% , and FEF_50% post-exercise compared to pre-exercise with HME. More respiratory symptoms overall were reported without HME (P = .046).

CONCLUSION

Intense cold air exercise likely causes transient acute bronchoconstriction and symptoms of cough in individuals participating in winter sports. However, this study finds that the application of an HME during intense cold air exercise improves lung function and reduces prevalence of EIB-associated symptoms compared to unprotected intense cold air exercise.

[German Language Version and Validation of the Risk-Taking Behaviour Scale (RBS-K) for High-Risk Sports]

BACKGROUND

 High-risk sports, particularly climbing, kayaking and extreme skiing, have become increasingly popular. The most widely used psychological survey instrument with regard to risk behaviour in sports is the Sensation Seeking Model, mostly assessed by the Sensation Seeking Scale (SSS-V). Until recently, the literature discussed risk behaviour solely through this model. However, this scale does not measure risk-taking behaviours. In contrast, the Risk-Taking Behaviour Scale (RBS-K) is a three-item scale that measures risk behaviour in high-risk sports. This study aimed to validate a German language version of the RBS-K.

METHODS

 The RBS-K was translated and back-translated between English and German. High-risk sports participants (n = 2399) completed the German version of the RBS-K. Of those participants, 820 completed the RBS-K in person as part of a field survey and 1579 participated in an online survey. To validate the questionnaire, the SSS-V, accident involvement, age and sex were evaluated. The RBS-K divides the sample into deliberate risk takers (mean + standard deviation) and risk-averse persons (mean - standard deviation). We tested for internal consistency and correlations with SSS-V, age, sex and accident involvement. Group differences were calculated between deliberate risk takers and risk-averse persons.

RESULTS

 For internal consistency, we obtained a Cronbach's alpha of 0.56 and a McDonald's omega of 0.63. Significant correlations were shown between RBS-K and SSS-V as well as age and sex. Compared to risk-averse persons (n = 643, 26.8 %), deliberate risk takers (n = 319, 13.3 %) scored significantly higher in sensation seeking, were significantly younger and primarily male and had a significantly higher accident involvement.

CONCLUSION

 The RBS-K discriminates well for age, sex and accident involvement. Also, correlations between the RBS-K and the well-established SSS-V are acceptable. With regard to the results and its compact design, the scale seems to be well suited for field surveys. We discuss the relatively modest internal consistency in the context of the small number of items and the different dimensions of risk-taking.

Factors Associated with Physical Fitness among Overweight and Non-Overweight Austrian Secondary School Students

The aim of the study was to evaluate factors associated with physical fitness (PF) among overweight and non-overweight Austrian secondary school students. PF was measured using the German motor test (DMT) 6-18 and students were asked about sex, migration background, weekly leisure time physical activity and daily electronic media use. In total 560 adolescents (56.6% female) with a mean age of 15.4 ± 1.4 years and a mean body mass index (BMI) of 22.5 ± 4.2 kg/m² were evaluated with 130 (23.2%) students classified as overweight or obese. For the total cohort, results of the multiple linear regression analysis (R2 = 0.34) revealed that a younger age (β = -0.16), no migration background (β = 0.13), a lower BMI (β = -0.29), a higher weekly leisure time physical activity (β = 0.34) and a lower daily electronic media use (β = -0.15) were associated with increased PF. Separate regression analyses for non-overweight and overweight students showed similar regression coefficients except for BMI. In conclusion, the positive influence of modifiable factors such as lower BMI, higher self-reported weekly leisure time sports activity and lower self-reported daily electronic media use should be considered already at young ages to increase physical fitness in overweight and non-overweight youth.

Are Risk-Taking and Ski Helmet Use Associated with an ACL Injury in Recreational Alpine Skiing?

According to the risk compensation hypothesis, the use of a ski helmet might provide a false sense of security, resulting in a riskier behavior by skiing faster or more aggressively, which might lead to an increased injury risk. Injury of the anterior cruciate ligament (ACL) is a common diagnosis in downhill skiers. Thus, the aim of the study was to evaluate the potential impact of risk-taking and ski helmet use on ACL injury risk in recreational skiing. Eighty-two ACL injured and 446 uninjured skiers with a mean age of 37.3 ± 11.9 years (52% females) were surveyed during the winter season 2018/19 about age, sex, self-reported risk-taking behavior, self-reported skill level, perceived speed, and ski helmet use. Multiple regression analysis revealed that older age (OR: 1.3, 95% CI: 1.2–1.4), riskier behavior (OR: 5.4, 95% CI: 2.8–10.5), and lower skill level (OR: 6.7, 95% CI: 3.4–13.3) were found to be factors associated with ACL injury, while ski helmet use was not. In conclusion, no support for the risk compensation hypothesis was found with regard to ACL injuries. Therefore, we doubt that ski helmet use increases the risk for ACL injury and recommend wearing a ski helmet due to reported protective effects.

Effects of Visual and Auditory Perturbations on Ski-Specific Balance among Males and Females-A Randomized Crossover Trial

Injuries in skiing show sex-specific differences, especially when visual perception is reduced. Reduced visual perception impairs balance, which plays an important role in avoiding skiing injuries. However, males and females might cope differently with reduced visual perception. Thus, the aim of this study was to evaluate sex-related effects of environmental perturbations (reduced visual perception and listening to music) on ski-specific balance. Using a crossover design, ski-specific balance was tested in 50 young adults (50% female) in four conditions: with and without listening to music and/or with and without reduced visual perception (ski goggles with occlusion foil). A four × two (condition by sex) mixed ANOVA revealed a significant condition by sex interaction, partial η² = 0.06. Females showed an increase in balance from the condition without music/with normal visual perception to the condition with music/with normal visual perception, while males showed a decrease. Balance was significantly higher in females compared to males, partial η² = 0.31. The findings suggest that balance is affected differently by environmental perturbations in females and males. However, the differences observed were not in line with our initial hypotheses, which might be because the model was too simplistic for how visual/auditory perturbations may affect balance.

Is the Effect of Physical Activity on Quality of Life in Older Adults Mediated by Social Support?

Increasing evidence suggests positive associations between physical activity, social support, and quality of life in later life. However, the role of physical activity and social support in the influence on quality of life is unclear. In this viewpoint, definitions of central terms and key research findings on factors influencing quality of life in older adults are provided. We highlight the importance of both a physically active lifestyle and high social support in positively influencing quality of life. However, we question the direct effect of physical activity on quality of life and present data of a cross-sectional study to support the assumption that the effect of physical activity on quality of life might be influenced by perceived social support. In this cross-sectional study, self-reported physical activity, social support, and quality of life were assessed in a nonclinical sample of 100 adults aged between 60 and 80 years. Statistical analyses included correlation analyses and covariate-controlled mediation analyses. The results confirmed the research findings on positive correlations between all domains of quality of life and both physical activity and social support. Mediation analyses indicated that the effect of physical activity on all domains of quality of life was at least partially mediated by social support, when controlled for covariates. Based on the findings of published evidence and this cross-sectional study, a socially and physically active lifestyle is recommended for older adults to positively influence quality of life. However, the well-documented effect of physical activity on quality of might be an at least partially mediated effect by perceived social support. Practical and research-related implications of a potential indirect effect are discussed. Further prospective research is warranted to clarify the relationship between the variables.

Biomineralization of strontium and barium contributes to detoxification in the freshwater alga Micrasterias

The unicellular model alga Micrasterias denticulata inhabits acid peat bogs that are highly endangered by pollutants due to their high humidity. As it was known from earlier studies that algae like Micrasterias are capable of storing barium naturally in form of BaSO₄ crystals, it was interesting to experimentally investigate distribution and sequestration of barium and the chemically similar alkaline earth metal strontium. Additionally, we intended to analyze whether biomineralization by crystal formation contributes to diminution of the generally toxic effects of these minerals to physiology and structure of this alga which is closely related to higher plants. The results show that depending on the treatment differently shaped crystals are formed in BaCl₂ and Cl₂Sr exposed Micrasterias cells. Modern microscopic techniques such as analytical TEM by electron energy loss spectroscopy and Raman microscopy provide evidence for the chemical composition of these crystals. It is shown that barium treatment results in the formation of insoluble BaSO₄ crystals that develop within distinct compartments. During strontium exposure long rod-like crystals are formed and are surrounded by membranes. Based on the Raman signature of these crystals their composition is attributed to strontium citrate. These crystals are instable and are dissolved during cell death. During strontium as well as barium treatment cell division rates and photosynthetic oxygen production decreased in dependence of the concentration, whereas cell vitality was reduced only slightly. Together with the fact that TEM analyses revealed only minor ultrastructural alterations as consequence of relatively high concentrated BaCl₂ and Cl₂Sr exposure, this indicates that biomineralization of Sr and Ba protects the cells from severe damage or cell death at least within a particular concentration range and time period. In the case of Sr treatment where ROS levels were found to be elevated, hallmarks for autophagy of single organelles were observed by TEM, indicating beginning degradation processes.

Preparation for Endurance Competitions at Altitude: Physiological, Psychological, Dietary and Coaching Aspects. A Narrative Review

It was the Summer Olympic Games 1968 held in Mexico City (2,300 m) that required scientists and coaches to cope with the expected decline of performance in endurance athletes and to establish optimal preparation programs for competing at altitude. From that period until now many different recommendations for altitude acclimatization in advance of an altitude competition were proposed, ranging from several hours to several weeks. Those recommendations are mostly based on the separate consideration of the physiology of acclimatization, psychological issues, performance changes, logistical or individual aspects, but there is no review considering all these aspects in their entirety. Therefore, the present work primarily focusses on the period of altitude sojourn prior to the competition at altitude based on physiological and psychological aspects complemented by nutritional and sports practical considerations.

Long-term effect of migration background on the development of physical fitness among primary school children

BACKGROUND

Children with a low socioeconomic status and migration background are more likely to exhibit unfavorable health behavior patterns and higher BMI scores as well as lower physical activity and physical fitness.

AIM

To evaluate the effect of migration background on the development of physical fitness among primary school children from first to third grade.

METHODS

In this longitudinal study, height, weight, and physical fitness of primary school children from Tyrol/Austria were measured five times over a period of 2.5 years using the German motor performance test DMT 6-18 consisting of eight items testing different subdomains of physical fitness.

RESULTS

A total of 266 children (45% girls) participated in all five tests, of which 69 (26%) children reported to have a migration background (MB). Mixed-model ANOVA did not reveal a significantly different development of physical fitness (according to the mean total Z-score of DMT 6-18) over time, P = 0.883, partial ƞ²  < 0.01. However, children with MB showed significantly lower physical fitness compared to children without MB, P < 0.001, partial ƞ²  = 0.06. Controlling for BMI and age did not alter the interpretation of the results. Analyses of the single test items revealed significant differences in motor tests involving strength and endurance.

CONCLUSION

Primary school children with and without MB significantly increased their physical fitness over time in a comparable manner. However, children with MB showed a significantly lower physical fitness at all test time points, which was only partly explained by a higher mean BMI in children with MB. Children with MB outreached the mean baseline fitness level of children without MB not until the fourth test time point, that is after two years. Therefore, a special focus on physical fitness particularly including strength and endurance capacities should be directed to children with MB already in young ages.

Alcohol Consumption and Physical Activity in Austrian College Students-A Cross-Sectional Study

BACKGROUND

The age of college students is considered as crucial for developing health-related behaviors, e.g., alcohol consumption or a physically active lifestyle. Previous research reported a positive relationship between alcohol consumption and physical activity (PA) in college students. However, the main body of research was done in students from the United States who might differ from European students.

OBJECTIVES

Thus the aim of this study was to analyze the relationship between alcohol consumption and PA in a sample of Austrian college students.

METHODS

In a cross-sectional design, 861 Austrian students from various study fields responded to a web-based questionnaire. Self-reported alcohol consumption, PA, and relevant sociodemographic variables were assessed. Multiple regression analyses were used to study the relationship between alcohol consumption and PA.

RESULTS

In none of the regression models, a significant relationship between alcohol consumption and PA was found. There was a significant influence of sex, age, relationship status, education level, and study field on alcohol consumption. Male, older, and undergraduate students studying social sciences without a relationship reported higher alcohol consumption. Conclusions/Importance: The results do not support a general relationship between alcohol consumption and PA among urban Austrian college students of various study fields. Compared to other variables (e.g., sex, relationship status), PA seems to be less important in relation to the consumption of alcohol. This study challenges a global perspective on a positive relationship between alcohol consumption and PA and highlights the need for more cross-cultural investigations.

Development of physical fitness in Austrian primary school children : A longitudinal study among overweight and non-overweight children over 2.5 years

Background

Physical activity and physical fitness play an important role in the prevention of overweight and obesity in childhood and adolescence and reduce the risk of becoming overweight or obese in adulthood.

Aim

To evaluate the development of physical fitness in overweight and non-overweight primary school children from the first to third grades.

Methods

Using a longitudinal study design, body height and weight as well as physical fitness of primary school children from Tyrol, Austria were measured five times during a period of 2.5 years using the German motor performance test (DMT 6–18).

Results

In total, 266 children (55% boys) with a mean age of 6.4 ± 0.5 years at baseline participated. The proportion of overweight children was 11% at baseline and 22% at the fifth time point. Overweight children showed a significantly lower physical fitness level (mean total z‑score of DMT6–18) at all 5 time points (Hedges g: 0.64–1.09). Repeated measurement analyses of variances showed a significant increase of physical fitness over time among overweight (partial η²: 0.12) and non-overweight (partial η²: 0.29) children. With respect to gender, physical fitness significantly increased over time among overweight (partial η²: 0.20) and non-overweight (partial η²: 0.28) girls, as well as among non-overweight boys (partial η²: 0.31) but not among overweight boys (partial η²: 0.07).

Conclusion

Overweight and non-overweight primary school children significantly increased their physical fitness over the study period; however, overweight children showed a significantly lower physical fitness level at all test time points and did not even achieve the mean baseline fitness level of non-overweight children. With respect to the increasing percentage of overweight children over the study period, evidence-based preventive measures to reduce overweight and increase physical fitness should be implemented at the earliest in primary schools with a special focus on overweight boys.

Fall-related accidents among hikers in the Austrian Alps: a 9-year retrospective study

Objective

To analyse the circumstances of fatal and non-fatal mountain hiking accidents caused by falls.

Methods

The study was designed as a retrospective analysis. Mountain hiking accidents caused by falls were documented during a 9-year period (2006–2014). After screening of all data for potential exclusion criteria the final sample size of 5368 accidents and 5665 victims was included into the analyses. Main outcome measures were details about accidents, victims, type of trail and surface.

Results

The annual number of accidents showed a continuous increase from 467 in 2006 to 700 in 2014. In total, 5.8% of all victims died during the 9-year period. 75.3% of the hikers fell during descent and 80.9% of the victims had their accident on a marked hiking trail or small path. The sex ratio for non-fatal accidents was 55% female and 45% male; for fatal accidents the female-to-male ratio was 28%:72%. Mean age of all victims was 52.5±17.5 years and victims of fatalities were about 5 years older compared with victims of non-fatal accidents (57.5±16.5 vs 52.2±17.5 years, P<0.01).

Conclusion

Descent is the most risky part for accidents caused by falls during mountain hiking. Male hikers are at greater risk for fatalities independent of age and this is associated with accidents occurring in pathless terrain. The death rate from falls was 6%. We recommend a critical self-assessment of the individual capabilities and mountain hiking skills and adequate planning of the hiking tours for mountain hikers.

Seven Passive 1-h Hypoxia Exposures Do Not Prevent AMS in Susceptible Individuals

PURPOSE

The present study evaluated the effects of a preacclimatization program comprising seven passive 1-h exposures to 4500-m normobaric hypoxia on the prevalence and severity of acute mountain sickness (AMS) during a subsequent exposure to real high altitude in persons susceptible to AMS.

METHODS

The project was designed as a randomized controlled trial including 32 healthy female and male participants with known susceptibility to AMS symptoms. After baseline measurements, participants were randomly assigned to the hypoxia or the control group to receive the preacclimatization program (seven passive 1-h exposures within 7 d to normobaric hypoxia or sham hypoxia). After completing preacclimatization, participants were transported (bus, cog railway) to real high altitude (3650 m, Mönchsjoch Hut, Switzerland) and stayed there for 45 h (two nights). Symptoms of AMS and physiological responses were determined repeatedly.

RESULTS

AMS incidence and severity did not significantly differ between groups during the high-altitude exposure. In total, 59% of the hypoxia and 67% of the control group suffered from AMS at one or more time points during the high-altitude exposure. Hypoxic and hypercapnic ventilatory responses were not affected by the preacclimatization program. Resting ventilation at high altitude tended to be higher (P = 0.06) in the hypoxia group compared with the control group. No significant between-group differences were detected for heart rate variability, arterial oxygen saturation, and hematological and ventilatory parameters during the high-altitude exposure.

CONCLUSION

Preacclimatization using seven passive 1-h exposures to normobaric hypoxia corresponding to 4500 m did not prevent AMS development during a subsequent high-altitude exposure in AMS-susceptible persons.

Prevalence of Mental Health Problems and Factors Associated with Psychological Distress in Mountain Exercisers: A Cross-Sectional Study in Austria

Knowledge about potential protective factors against mental health problems is highly needed. Regular physical activity (PA) in an outdoor environment, like mountain exercising, might reduce psychological distress. Therefore, the aims of the present study were to assess the prevalence of mental health problems in mountain exercisers and to detect factors associated with psychological distress. In a cross-sectional design, we collected self-reported data of 1,536 Austrian mountain exercisers. The prevalence of mental health problems and psychological distress (Kessler Psychological Distress Scale), the level of PA International Physical Activity Questionnaire, and affective valence during PA (Feeling Scale) were obtained. Stepwise multiple linear regression analysis was conducted to assess factors influencing psychological distress. The prevalence of mental health problems in Austrian mountain exercisers was 14%. Health-enhancing PA level and higher affective valence during PA were significantly associated with lower psychological distress. Minimal PA level was not significantly associated with lower psychological distress compared to inactive PA level. Marital status, education, alpine association membership, and body mass index did not show a significant influence on psychological distress. The prevalence of mental health problems seems to be lower in Austrian mountain exercisers compared to the European population. A health-enhancing PA level and affective valence increasing forms of PA were shown to be associated with lower psychological distress. Results might lead to interventional studies focusing on the potential of outdoor PA, e.g., mountain exercise, as an adjunct treatment in people at risk or with mental health problems.

Immediate affective responses of gait training in neurological rehabilitation: A randomized crossover trial

OBJECTIVE

To examine the immediate effects of physical therapy and robotic-assisted gait training on affective responses of gait training in neurological rehabilitation.

DESIGN

Randomized crossover trial with blinded observers.

PATIENTS

Sixteen patients with neurological disorders (stroke, traumatic brain injury, spinal cord injury, multiple sclerosis).

METHODS

All patients underwent 2 single treatment sessions: physical therapy and robotic-assisted gait training. Both before and after the treatment sessions, the self-report Mood Survey Scale was used to assess the effects of the treatment on distinct affective states. The subscales of the Mood Survey Scale were tested for pre-post changes and differences in effects between treatments, using non-parametric tests.

RESULTS

Fourteen participants completed the study. Patients showed a significant increase in activation (r = 0.55), elation (r = 0.79), and calmness (r = 0.72), and a significant decrease in anger (r = 0.64) after robotic-assisted gait training compared with physical therapy.

CONCLUSION

Affective responses might be positively influenced by robotic-assisted gait training, which may help to overcome motivational problems during the rehabilitation process in neurological patients.

Affective responses in mountain hiking-A randomized crossover trial focusing on differences between indoor and outdoor activity

INTRODUCTION

Affective responses during physical activity (PA) are important for engagement in PA programs and for adherence to a physically active lifestyle. Little is known about the affective responses to PA bouts lasting longer than 45 minutes. Therefore, the aims of the present study were to analyse acute effects on affective responses of a three-hour outdoor PA intervention (mountain hiking) compared to a sedentary control situation and to an indoor treadmill condition.

METHODS

Using a randomized crossover design, 42 healthy participants were randomly exposed to three different conditions: outdoor mountain hiking, indoor treadmill walking, and sedentary control situation (approximately three hours each). Measures included the Feeling Scale, Felt Arousal Scale and a Mood Survey Scale. Repeated measures ANOVAs were used to analyse differences between the conditions.

RESULTS

Compared to the control situation, the participants showed a significant increase in affective valence (d = 1.21, p < .001), activation (d = 0.81, p = .004), elation (d = 1.07, p < .001), and calmness (d = 0.84, p = .004), and a significant decrease in fatigue (d = -1.19, p < .001) and anxiety (d = -.79, p < .001) after mountain hiking. Outdoor mountain hiking showed significantly greater positive effects on affective valence, activation, and fatigue compared to indoor treadmill walking.

DISCUSSION

The results indicate that a three-hour PA intervention (mountain hiking) elicits higher positive and lower negative affective responses compared to a sedentary control situation and to an indoor PA condition. Outdoor mountain hiking can be recommended by health professionals as a form of PA with the potential to positively influence affective responses.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02853760. https://clinicaltrials.gov/. Date of registration: 08/02/2016 (retrospectively registered). Date of enrolment of the first participant to the trial: 05/01/2014.

Is decision making in hypoxia affected by pre-acclimatisation? A randomized controlled trial

INTRODUCTION

Decision making is impaired in hypoxic environments, which may have serious or even lethal consequences for mountaineers. An acclimatisation period prior to high altitude exposures may help to overcome adverse effects of hypoxia. Thus, we investigated possible effects of short-term pre-acclimatisation on decision making in hypoxia.

METHODS

In a randomized controlled study design, 52 healthy participants were allocated to a hypoxia group (HG: short-term pre-acclimatisation by the use of intermittent hypoxia 7×1h at F_iO₂=12.6%, equivalent to 4500m) or a control group (CG: sham pre-acclimatisation 7×1h at F_iO₂=20.9%, equivalent to 600m). The number of risky decisions was assessed using the Game of Dice Task at four time points during a 12-hours stay in hypoxia (F_iO₂=12.6%).

RESULTS

42 (HG: 27, CG: 25) participants completed the study. The number of risky decisions was significantly (p=0.048 as determined by 4×2 ANCOVA) reduced in the hypoxia group compared to the control group, partial η²=0.11, when the age-effect on decision making was controlled. Self-reported positive affective valence prior to decision making was negatively related to the number of risky decisions, r<-0.38.

CONCLUSION

Short-term pre-acclimatisation might influence decision making in hypoxia in a positive way and might be considered as a risk-reducing preparation method prior to exposures to hypoxic environments. Positive affective states seem to have a medium-sized protective effect against risky decision making.

Is acute mountain sickness related to trait anxiety? A normobaric chamber study

INTRODUCTION

Some mountaineers are more prone to the occurrence of acute mountain sickness (AMS) than others. State anxiety during altitude exposure might be associated with AMS development. We hypothesized that trait anxiety might be higher in AMS cases compared to non-AMS cases. The aim of the present study was to study the relationship between AMS development and trait anxiety.

METHODS

In an observational study design, AMS incidence during a 12-hour exposure to normobaric hypoxia (F_iO₂=12.6%, equivalent to 4500m) was determined by the Lake Louise Scoring System. Trait anxiety (State Trait Anxiety Inventory) and confounding variables were assessed in a follow-up questionnaire (37months after hypoxic exposure).

RESULTS

Twenty nine participants returned the follow-up questionnaire. AMS incidence was 38%. Both unadjusted and adjusted logistic regression analyses did not reveal trait anxiety as a significant variable in relation to AMS.

DISCUSSION

Based on the findings of this preliminary study, there is no evidence that AMS development under normobaric conditions is related to trait anxiety. Differences to previous studies might be explained by the type of hypoxia, by different sample characteristics and by considering sleep disturbances in the calculation of the AMS score. However, future studies with larger sample sizes may help to clear the relationship between AMS development and the personality factor anxiety.

Predictors of doping intentions, susceptibility, and behaviour of elite athletes: a meta-analytic review

Research in doping has focused on potential intervention strategies, increasingly targeting predicting factors. Yet, findings are inconsistent, mostly athlete-centred and explain only limited variances in behaviour. This critical review aims to (a) summarize studies that identified predictors of doping intentions, susceptibility, and behaviour in elite athletes and to (b) analyse in how far previous research included aspects beyond athlete-centred approaches, such as context and sporting culture. We reviewed 14 studies that focused on elite athletes. Situational temptation, attitudes, and subjective norms seem to be strong predicting variables of doping intentions (r ≥ 0.50), but intention was no predictor for behaviour. Attitudes were a significant predictor for both, doping susceptibility (r = 0.47) and behaviour (r = 0.30). Most of the predictors are athlete-centred and ignore macro-level factors that might help to explain how certain individual traits impact on the decision making process. The findings from this review call for a critical discussion of whether current doping-prevention research needs to take new directions. We propose future research to bridge findings of psychologists and sociologists, as it appears that doping behaviour cannot be explained by ignoring the one or the other. Impacts of sporting culture that have been identified in qualitative approaches need to be integrated in future quantitative approaches to test for its external validity. Inclusion of both, micro- and macro level factors may enable an integrative prevention program that creates a sporting culture without doping.

Expression of the AtSUC1 gene in the female gametophyte, and ecotype-specific expression differences in male reproductive organs

Based on analyses in Arabidopsis thaliana ecotype C24, the AtSUC1 protein was previously characterised as a male gametophyte-specific H(+)/sucrose symporter. Later, expression analyses in ecotype Columbia-0 (Col-0) identified AtSUC1 expression also in trichomes (not detected in trichome-less C24 plants) and roots, suggesting ecotype-specific differences in AtSUC1 expression. Here, we present data on additional ecotype-specific differences in AtSUC1 expression in other tissues. Using different AtSUC1 promoter-reporter gene lines, we performed comparative analyses of AtSUC1 expression in floral tissues of C24 and Col-0 plants, and using an AtSUC1-specific antiserum, we performed immunohistochemical analyses on tissue sections from C24, Col-0, Landsberg erecta (Ler) and Wassilewskaija (Ws) ecotypes. We show that AtSUC1 expression occurs in the funicular epidermis of C24, Ler and Ws, but not in Col-0. In contrast, we observed high levels of AtSUC1 protein in pollen grains of Col-0, lower levels in pollen of C24 and Ler, and no AtSUC1 protein in Ws pollen. Moreover, our reporter gene analyses identified a previously undetected expression of AtSUC1 in the female gametophyte, and revealed that AtSUC1 expression in the funicular epidermis is absent from unpollinated siliques and is induced upon successful pollination. The impact of these findings on the potential physiological role of AtSUC1 is discussed.