Impact of a 3-Day High-Altitude Trek on Xue Mountain (3886 m),Taiwan,on the Emotional States of Children: A Prospective Observational Study

Abstract

Aims:

Changes in emotions associated with mountain treks have rarely been reported. This study examined emotional state changes in sixth-grade elementary school students before and after a 3-day high-altitude mountain trek from the trailhead (2140 m) to Xue Mountain (3886 m) in Taiwan.

Methods:

In June 2011, 201 students participated in the trek. The round-trip distance was 21.8 km. The age, gender, blood group, and family configuration of the participants were documented before the trek. A 36-item short-form survey instrument, including the Mood and Anxiety Symptom Questionnaire and the Positive and Negative Affect Scale for Children, was used to evaluate the participants' emotional states (happiness, anticipation, sadness, and anger). The participants answered the questionnaires 1 month before and 1 week after the trek. A Likert scale was used to evaluate individual items (range 1–4; from strongly disagree to strongly agree). We calculated scores for each index before and after the trek. The incidence and presentation of acute mountain sickness (AMS) among the participants was also studied and published previously.

Results:

In total, 187 (112 boys and 75 girls) participants (mean age 11.9 ± 0.4 years) completed the trek and the survey. The sadness and anger scores (negative emotions) were significantly lower after than before the trek (39.5 vs. 36.6; p < 0.01). The happiness and anticipation scores (positive emotions) before and after the trek did not differ significantly (49.9 vs. 48.9; p = 0.11). No participant used AMS prophylaxis, while 78 participants met the AMS criteria. Negative emotions decreased more in those with AMS than without AMS (−4.6 vs. −1.8; p = 0.04), and the use of medications or acetazolamide did not alter the emotions.

Conclusions:

A 3-day high-altitude mountain trek can reduce children's negative emotions. Negative emotions decreased more in those with AMS, whereas medications or acetazolamide did not alter their emotions.

Introduction

Exposure to high altitudes above 3000 m (9843 ft) for several hours to several days can cause physical stress in individuals. The risk of hypoxia and high-altitude illness is associated with an increase in altitude. People who develop high-altitude illness during a high-altitude trek sometimes need to be rescued, and the incidence rate of acute mountain sickness (AMS) is higher in children than in adults (Wang and Huang, 2013; Wu et al., 2015).

Changes in mood associated with high-altitude activities have rarely been studied. Altitudes >4000 m are reported to exert visible effects on mood, behavior, and cognitive functions (Shukitt-Hale et al., 1991).

Many studies have focused on factors that can affect the mood of children or adolescents in low-altitude settings, whereas other studies have highlighted the emotional states of adults or soldiers at high altitudes (Shukitt and Banderet, 1988; Shukitt-Hale et al., 1990). Mountain trekking is an activity that requires both physical and mental well-being. An increasing number of 11–13-year-old children have attempted high-altitude mountain treks in recent years, and AMS has been extensively studied in children at high altitudes (Wang and Huang, 2013; Wu et al., 2015). However, to the best of our knowledge, no study has investigated the impact of high-altitude mountain treks on changes in the emotional states of children.

In this study, the highest point that participants reached was 3886 m. We evaluated the emotional states of sixth-grade elementary school students before and after a 3-day high-altitude mountain trek.

Materials and Methods

In June 2011, 201 sixth-grade elementary school students participated in a high-altitude mountain trek spanning 3 days and 2 nights from the trailhead (2140 m) to the summit of Xue Mountain (3886 m). The round-trip distance of the trail was 21.8 km. No participant was involved in designing research questions or outcome measures or in planning or conducting the study. Moreover, no participant was involved in data interpretation or report writing.

Demographic information pertaining to the age, gender, blood group, and family configuration of the participants was documented before the trek. A 36-item short-form survey instrument, including the Mood and Anxiety Symptom Questionnaire (Buckby et al., 2007) developed by Chang and Yeh, and the Positive and Negative Affect Scale for Children developed by Watson and Clark (1997), was used to evaluate the participants' emotions, with the scores ranging from 36 to 144 (Appendix 1). Specifically, four emotional states (happiness, anticipation, sadness, and anger) were assessed using indices; 12, 10, 9, and 5 questions were related to happiness (score 12–48), sadness (score 10–40), anger (score 9–36), and anticipation indices (score 5–20), respectively. The participants answered the questionnaires 1 month before (evaluation 1) and 1 week after the trek (evaluation 2).

A Likert scale ranging from 1 to 4 was used to evaluate individual items (1, strongly disagree; 2, disagree; 3, agree; and 4, strongly agree). We calculated each index and compared individual differences between the two evaluations. The protocol was approved by the Institutional Review Board of Chang Gung Memorial Hospital, and written informed consent was obtained from all the participants and their parents before the questionnaires were distributed.

Moreover, the incidence rate and symptom presentations of AMS were also studied among the participants, and these data were published in our previous study (Cheng et al., 2017). AMS was evaluated using the Lake Louise Questionnaire (LLQ), which included headache, dizziness or lightheadedness, fatigue or weakness, gastrointestinal (GI) symptoms (nausea, vomiting, and loss of appetite), and sleep disturbance. Each symptom was scored from 0 to 3 (0, 1, 2, and 3 representing no, mild, moderate, and severe and incapacitating symptoms, respectively). We also analyzed the relationship between AMS and each emotional state, and recorded the participants' use of medication for AMS or related symptoms.

Statistical analysis

Data for continuous variables are expressed as mean ± standard deviation or median (range), whereas those for categorical variables are expressed as percentages. Continuous data from the two groups (1 month before and 1 week after the trek: evaluation 1 vs. evaluation 2) were compared using paired t-tests, and the Wilcoxon rank-sum test was used when data were highly skewed. An independent sample t-test was used to determine the differences in scores for each emotional state in AMS and non-AMS group. Pearson's correlations were used to determine relationships between the emotional states and the consistency of the indices. A p-value <0.05 was considered statistically significant, and all analyses were performed using SPSS statistical software for Windows, version 19.0 (SPSS, Chicago, IL).

Results

In total, 201 participants were recruited, but only those who completed the trek and both questionnaires (before and after the trek) were enrolled in the study. According to the inclusion criteria, 14 participants were excluded (12 did not provide informed consent and 2 failed to complete both questionnaires), which yielded a final sample size of 187 participants (Fig. 1). A descriptive summary of the participants' characteristics is presented in Table 1. The sample consisted of 112 (59.9%) boys and 75 (40.1%) girls. The mean age of the participants was 11.9 ± 0.4 years. The results revealed several differences in the emotional states of the participants before and after the trek (Table 2). Although no significant differences were noted in their positive emotion scores (on happiness and anticipation indices) before and after the trek (49.9 vs. 48.9; p = 0.11), their negative emotion scores (on sadness and anger indices) were significantly lower after (39.5 vs. 36.6; p < 0.01) than before the trek.

FIG. 1.

Flowchart of the enrollment process.

Table 1.

Baseline Characteristics of Participants

	Total (N = 187)	Percentage
Age (years)	11.9 ± 0.4
Gender
Male	112	59.9
Female	75	40.1
Body weight (kg)	45.1 ± 11.0
Body height (cm)	153.2 ± 7.4
Father's education
Elementary school	1	0.5
Junior high school	3	1.6
Senior high school	24	12.8
College	18	9.6
University	84	44.9
Graduate school	36	19.3
PhD	18	9.6
Other	3	1.60
Mother's education
Junior high school	5	2.7
Senior high school	25	13.4
College	26	13.9
University	89	47.6
Graduate school	32	17.1
PhD	7	3.7
Other	3	1.6
All siblings
First child	115	61.5
Second child	48	25.7
Third child	18	9.6
Fourth child	6	3.2
Live with
Both parents	138	73.8
Mother only	12	6.4
Father only	1	0.5
Grandparents	1	0.5
Other relatives	35	18.7

Continuous data are expressed as number, mean ± standard deviation, or median (range), while categorical data are expressed as percentage.

Table 2.

Emotional State Scores Before and After the 3-Day High-Altitude Mountain Trek (N = 187)

	Before (95% CI)	After (95% CI)	p
Positive	49.9 ± 10.4 (34.8–37.2)	48.9 ± 10.1 (47.5–50.3)	0.11
Negative	39.5 ± 11.6 (37.8–41.2)	36.6 ± 10.4 (35.1–38.1)	<0.01
Total
Happiness index	36.0 ± 8.3 (34.8–37.2)	35.0 ± 7.0 (34.0–36.0)	0.07
Anticipation index	13.9 ± 2.9 (13.5–14.3)	13.9 ± 3.3 (13.4–14.3)	0.87
Sadness index	20.3 ± 6.3 (19.3–21.2)	18.6 ± 5.6 (17.8–19.4)	<0.01
Anger index	19.3 ± 5.7 (18.4–20.1)	17.9 ± 5.4 (17.2–18.7)	<0.01

Data are expressed as mean ± standard deviation with 95% CI. A paired t-test was used to determine differences in scores for each emotional state before and after the 3-day high-altitude mountain trek. A p-value <0.05 was considered statistically significant.

CI, confidence interval.

The happiness scores decreased from 36.0 to 35.0 (p = 0.07; positive emotional states; Table 2), and anticipation scores changed from 13.9 to 13.9 (p = 0.87; positive emotional states; Table 2) after the trek. The sadness scores significantly decreased from 20.3 to 18.6 (−8.0%; p < 0.01; negative emotional states; Table 2). Similarly, the anger scores decreased significantly from 19.3 to 17.9 (−6.8%; p < 0.01; negative emotional states; Table 2) after the trek.

We also analyzed the changes in each emotional state between those with AMS and without AMS (Table 3). Interestingly, negative emotional states decreased more in those with AMS than those without AMS (−4.6 vs. −1.8; p = 0.04). Similar trends have been observed in sadness (−2.5 vs. −1.1; p = 0.09) and anger scores (−2.2 vs. −0.8; p = 0.048).

Table 3.

Change in Emotional Scores Between Participants With and Without Acute Mountain Sickness (N = 185)

Outcomes	AMS		p
Outcomes	Participants^a with AMS (N = 78)	Participants^a without AMS (N = 107)	p
Positive	−0.7 ± 7.4	−1.3 ± 9.3	0.65
Negative	−4.6 ± 10.8	−1.8 ± 7.8	0.04
Happiness	−0.5 ± 5.4	−1.3 ± 8.2	0.46
Anticipation	−0.2 ± 2.8	0.1 ± 2.5	0.59
Sadness	−2.5 ± 6.3	−1.1 ± 4.3	0.09
Angry	−2.2 ± 5.5	−0.8 ± 4.2	0.048

Data are expressed as mean ± standard deviation. An independent sample t-test was used to determine differences in scores for each emotional state before and after the 3-day high-altitude mountain trek. A p-value <0.05 was considered statistically significant.

Data of two participants were missed.

AMS, acute mountain sickness.

The correlation between the emotional states (happiness, anticipation, sadness, and anger) is shown in Table 4. The positive indices were strongly correlated with each other (r = 0.67; p < 0.01); similarly, the negative indices were strongly correlated with each other (r = 0.84; p < 0.01). The sadness and anger indices both showed strong negative correlations with the anticipation index (r = 0.25 and 0.31, respectively; p < 0.01). The correlation coefficients and p-values indicated that the questionnaires were highly consistent and reliable.

Table 4.

Correlation Coefficients Between Emotional States on Each Subscale

Variable	Happiness index	Anticipation index	Sadness index	Anger index
Happiness index	1
Anticipation index	0.67	1
Sadness index	0.47	0.25	1
Anger index	0.55	0.31	0.84	1

For all comparisons, p-values were all <0.01. Pearson's correlation was used to determine relationships between each emotional state and the consistency of questionnaires. A p-value <0.05 was considered statistically significant.

In our study, 78 participants met the criteria of AMS, and 172 participants had at least one AMS-associated symptom. We have also investigated and reported about the AMS incidences among this activity previously (Cheng et al., 2017). The most prevalent symptom in all the participants was sleep disturbance, followed by dizziness, headache, fatigue, and GI symptoms. We did not provide prophylactic medication unless the participants met the criteria for AMS (with headache and LLQ score ≥3). In total, 70 participants received medication during the trip. In the AMS group (n = 78), 44 participants were administered acetazolamide. In the non-AMS group (n = 107), 26 participants were administered either acetaminophen for headache or dysmenorrhea or metoclopramide for GI symptoms, such as nausea or vomiting. We further analyzed the effect of medication (n = 70) or acetazolamide (n = 44) on emotional scores, and concluded that there is no statistical significance between the two groups (Table 5).

Table 5.

Change in Emotional Scores Between Participants With and Without Medication and Acetazolamide (N = 184)

Outcomes	Medication		p
Outcomes	Used^a (N = 70)	Not used^a (N = 114)	p
Positive	−1.0 ± 8.9	−1.0 ± 8.4	0.95
Negative	−2.3 ± 9.3	−3.5 ± 9.2	0.42
Happiness	−1.1 ± 7.7	−0.9 ± 6.8	0.90
Anticipation	0.1 ± 2.6	−0.1 ± 2.6	0.56
Sadness	−0.9 ± 5.1	−2.1 ± 5.3	0.12
Angry	−1.4 ± 5.3	−1.3 ± 4.6	0.89

	Acetazolamide		p
	Used^a (N = 44)	Not used^a (N = 140)	p
Positive	−1.2 ± 6.8	−1.0 ± 9.1	0.86
Negative	−3.7 ± 10.6	−2.8 ± 8.8	0.56
Happiness	−1.2 ± 4.9	−0.9 ± 7.8	0.78
Anticipation	0.0 ± 2.7	−0.1 ± 2.6	0.85
Sadness	−1.6 ± 5.8	−1.7 ± 5.1	0.87
Angry	−2.2 ± 6.0	−1.1 ± 4.5	0.20

Data of three participants were missed.

Discussion

The emotional states of near-teenage children are affected by many factors and events during the course of maturation, including family relationships, peer interactions, and daily activities. Regular physical exercise was reported to improve the mental health of all age groups (Lawman et al., 2011). Sports, such as hiking and jogging, have long been considered healthy for the numerous benefits associated with them. Moreover, performing physical activities with peers was reported to enhance the psychological and social health of adolescents (Lind et al., 2008). Mountain trekking was beneficial for boosting self-esteem in students aged 18–23 years (Bahaeloo-Horeh and Assari, 2008). In recent years, many groups have advocated the incorporation of outdoor activities in adventure programs for senior individuals and patients with disabilities (Cotton and Butselaar, 2013; Daskivich et al., 2015). A previous study has reported that adventure-based training in day camps reduced depression and anxiety levels and increased self-esteem in primary school children (Li et al., 2013). Adventure therapy consists of a wide range of activities, including outdoor exercises and experiential learning activities, to help participants to cope with psychosocial issues. Adventure therapy can facilitate participants to develop cognitive skills, reduce behavioral problems (e.g., relationship problems involving their schools and families or social issues), ameliorate psychological problems (whether internalized or externalized), and enhance their resistance to stress (Cotton and Butselaar, 2013). These therapies include hiking, kayaking, participating in residential camps, and wilderness-based expeditions (Schell et al., 2012). Adventure and wilderness therapies are believed to exert positive and therapeutic effects on adolescents' mental health (Bowen et al., 2016). High-altitude mountain climbing, which is a combination of hiking and increasing altitude, is considered a suitable outdoor exercise.

High-altitude activities and exposure affect human beings on physiological and emotional levels (Shukitt and Banderet, 1988; Shukitt-Hale et al., 1990, 1991). Exercise can reduce anxiety and improve physical self-perception; in some cases, it could improve overall self-esteem (Fox, 1999). Adventure therapy and adventure-based training, such as rock climbing and canoeing, reduced the effects of negative moods (such as depression and anxiety) and increased the self-esteem of sixth-graders (Li et al., 2013). Adventure activities are characterized by the following features: (1) they are conducted in an unfamiliar natural environment; (2) they consist of challenges with clear goals and usually entail collaboration between individuals; (3) they are conducted in a small group setting; and (4) they are guided by experienced, skilled instructors who ensure the physical safety of participants and provide emotional support during the activity (Carlson and Cook, 2007).

Wang et al. reported an AMS incidence rate of 40.6%–59% in children (Wu et al., 2015; Chan et al., 2016; Cheng et al., 2017) compared with 36% in adult trekkers who climbed Jade Mountain (3952 m) in Taiwan (Wang et al., 2009); however, in another study, the incidence rate of AMS did not differ significantly between young people and adults (Stokes et al., 2009). In addition, differences in the age-related prevalence of AMS may be more significant (p < 0.001) at altitudes >3000 m (Hsu et al., 2015) than at low altitudes. The overall incidence of AMS was 40.6% in this age group, and 37% of children received medication during the entire trekking course (Cheng et al., 2017). Thus, trekking on a mountain with an altitude >3000 m within 3 days appears to be slightly more challenging for children in the age group of 11–13 years than for adults. However, many children aged between 11 and 13 years have attempted high-altitude mountain treks in recent years. To the best of our knowledge, studies on the effects of high-altitude mountain treks on changes in the emotional states of children have not been conducted thus far.

In our study, the sadness and anger scores both decreased significantly after the trek. However, the positive emotion scores (happiness and anticipation) did not significantly increase. Previous studies have shown that the initial mood change at high altitudes is euphoria, which is followed by depression. With time, individuals may become quarrelsome, irritable, anxious, and apathetic at high altitudes (Shukitt and Banderet, 1988; Shukitt-Hale et al., 1990, 1991). Similar to studies that focus on mood changes, only a few studies on cognitive functioning at high altitude are available. One study has shown that at an altitude ≥3000 m (9843 ft), cognitive performance decreases first, thus inducing physical symptoms and changes in moods (Shukitt-Hale et al., 1991). Finally, the overall performance decreases. Nonetheless, those studies were conducted on adults, and their sample sizes were small (Shukitt-Hale et al., 1990, 1991).

A previous study reported that while training a young group, an increase of 45% in fatigue and a decrease of 24% in energy were observed (Comotto et al., 2015). During early adolescence, peers, parents, and family represent some of the crucial factors affecting adolescent behavior (Ladd et al., 2014). In this activity, parents often participate in low-altitude training with students. However, during the Xue Mountain trek, the school policy strictly prohibited parents from accompanying their children throughout the journey. Positive effects of peer influence on eating behavior, body image, and mental health have also been reported (Helfert and Warschburger, 2013; Mundt and Zakletskaia, 2014); therefore, encouragement from peers was used as a support strategy during the trek. During the activity, only qualified professional guides and teachers were allowed to accompany the participants; the peers provided only encouragement when the participants encountered difficulties during the trek. Because trekking was a major challenge for the participants, motivation was highly crucial. By contrast, mountain climbing is usually associated with a high risk of injury, and one study reported that cooperation may reduce the risk of injury (Monasterio et al., 2014). Therefore, this prospective observational study emphasized teamwork and peer encouragement.

Negative moods, such as anxiety, can also be reduced by exercise (Chen et al., 2016). A positive mood or “runner's high” during exercise results from β-endorphin secretion in the brain (Boecker et al., 2008). Many studies have demonstrated the positive effects of regular exercise on mood (Levin et al., 2016). In our study, the short high-altitude mountain trek facilitated a change in the attitudes of the participants and reduced the levels of their negative emotions without increasing the levels of their positive emotions. Although one might logically predict that an experience with AMS might lead to much more negative feelings about the experience, negative emotions decreased more in those with AMS in our study. In participants with AMS, more attention and resources were allocated to ensure participants' safety and wellness during the trek. It is suspected that the care provided by medical personnel, teachers, and mountain guides, as well as the support from peers, may have contributed to a greater decrease in negative emotions for those with AMS. However, administration of medications for participants with AMS (acetazolamide) or other symptoms (acetaminophen or metoclopramide) did not alter their emotions.

A change in psychological processes may result from experiential learning. Mountain trekking consists of both adventure and exercise components. Studies have shown that performing aerobic exercises regularly reduces anxiety and depression not only in healthy individuals but also in patients with brain cancer, glioblastoma multiforme, and oligodendroglioma (Levin et al., 2016). Mountain trekking has long been considered an exercise that requires sound physical health and high determination levels (mental health). In this study, our high-altitude mountain trek met the criteria for such an activity. Our data before and after the trek showed that the trek significantly reduced the levels of negative emotions, as indicated by decreases in anger and sadness scores (both p < 0.00). However, the self-esteem component was not evaluated because positive emotion scores (happiness and anticipation indices) did not increase significantly after the trek.

The results of this study suggested that a 3-day high-altitude mountain trek reduced the levels of negative emotions among early adolescents. However, this activity must involve well-organized and planned activities that are supported by self and the families.

Study limitations

Our study has several limitations. First, the population of the study was not representative of the age-matched general population in Taiwan or other countries in the world. Several factors, such as family background, place of residence, and life experiences, may have affected the moods of early adolescents who participated in this study. Similar research should be conducted in other populations and ethnicities to verify the conclusions of our study. Second, because of the design of this study, we were unable to specifically analyze and compare mood changes among the participants with different rate of ascend or different levels of altitude tolerance during the 3-day mountain trek. Third, students do not typically have a medical team with them while trekking. In this study, a medical team ensured the safety of participants, and the medical team could take care of participants immediately whenever they experience AMS or related symptoms. The presence of health care professionals may have affected the mood of participants, making the study less ecologically valid. For example, the presence of the medical team may have reduced the level of sadness or increased the level of anticipation among the participants. We suggest that in future studies the effects of a mountain trek on emotional states in children be assessed in the absence of a medical team. Fourth, the trek required the participants to spend two nights without their family members, and physical separation from their family members may have increased the levels of sadness or anger and reduced the level of happiness of the participants. Furthermore, this study did not address issues related to mountain trekking activities that did not involve an overnight stay, and it did not examine the psychological states of children who were accompanied by parents during the activities. Moreover, to prevent delay in activity and prolonged exposure to high altitude, we did not distribute the questionnaires during the trek, which would have more accurately represented the participants' moods. Finally, we did not record emotional states during a similar trek at low altitudes; therefore, the relationship between similar activities at low altitudes and the emotional states of near-teenage students is unclear.

Conclusions

A high-altitude mountain trek spanning 3 days and 2 nights facilitated the reduction of negative emotions in sixth-grade elementary school students. Negative emotions decreased more in those with AMS, whereas medications or acetazolamide did not alter their emotions. Our study suggested that early adolescents should be encouraged to participate in safe multi-day activities, such as a 3-day high-altitude mountain trek.

Footnotes

Author Disclosure Statement

No competing financial interests exist.

Appendix 1: Questionnaire

Each question was rated on a scale of 1–4—1, strongly disagree; 2, disagree; 3, agree; and 4, strongly agree.

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