본 연구의 목적은 청소년의 운동시간의 변화가 자아존중감의 변화로 이어지는 관계에서 그릿의 변화의 매개효과를 검증하는 것이다. 한국아동·청소년패널 2018의 중1 코호트 2개년도 자료 중 결측치를 포함한 케이스를 제외한 2,438명(남=1,327명, 여=1,111명)의 자료가 분석에 활용되었다. 각 변인의 변화량 간의 관계를 검증하기 위해 1차년도 측정값과 2차년도 측정값의 회귀분석에서 생성된 표준화잔차점수를 변화량 변수로 활용하였다. 상관관계 분석 결과, 운동시간의 변화량과 자아존중감의 변화량, 그릿의 변화량은 모두 서로 유의한 정적상관이 있는 것으로 나타났다. 위계적 회귀분석을 통한 매개효과 검증 결과, 운동 시간의 변화가 그릿의 변화를 통해 자아존중감의 변화에 직·간접적으로 영향을 미치는 부분매개효과가 유의한 것으로 확인되었다. 이러한 결과는 운동시간의 감소가 청소년의 그릿과 자아존중감의 감소에 영향을 미친다는 것을 의미한다.

The purpose of this study was to assess visual biofeedback's influence on trunk muscles' (EMG) activity and endurance holding time for correct position during whole-body tilt exercise. For the study, we recruited 14 volunteers who showed no symptom of lumbar disease during medical tests. We measured the EMG activity of their rectus abdominis, external abdominal oblique, internal abdominal oblique and erector spinae muscles, and their endurance holding time for correct position during anterior and posterior whole-body tilt under two conditions: whole-body tilt with and without visual biofeedback. Resistance with gravitational force on the trunk during whole-body tilt was applied by using a device that had a monitor on which the subjects could check their alignment and that sounded an alarm if a subject's alignment collapsed. The study showed an increase in the EMG activity of external abdominal oblique, internal abdominal oblique/rectus abdominis ratio and endurance holding time for correct position during both anterior and posterior whole-body tilt with visual biofeedback compared with without visual biofeedback (p<.05). We suggest that the whole-body tilt exercise with visual biofeedback could be a beneficial strategy for selectively strengthening the internal abdominal oblique muscle and minimizing the rectus abdominis muscle's activity while maintaining correct alignment during whole-body tilt exercise.

This study examined the vastus medialis oblique (VMO) and the vastus lateralis (VL) onset time differences (OTD) during quadriceps contraction in different hip positions. Twelve healthy subjects were recruited (four men, eight women). Surface EMG activities of the VMO and VL were measured during a quadriceps strengthening exercise in a long sitting condition and in a sitting at a chair with feet hanging condition. For each condition, subjects were tested in two hip positions (neutral and adduction). The OTD between the two muscles was calculated for each condition, by subtracting the onset time of the VL from the VMO. Therefore, the negative value of OTD represent earlier EMG onset of the VMO compared to the VL. The OTD was not significantly different between the hip neutral and the hip adduction position in the long sitting condition (p=.064). However, the OTD was significantly different between the hip neutral position (15.83±109.51 ms) and hip adduction position (-5.58±121.08 ms) during the sitting at a chair with feet hanging condition (p=.047). The negative OTD value in the hip adduction condition during quadriceps strengthening exercises is the result of earlier onset of the VMO than VL. Therefore, quadriceps contraction in the hip adduction position can prevent the risk of patella lateral tracking. We expect that quadriceps strengthening exercise in the hip adduction position will be a safe way to prevent patellofemoral pain syndrome resulting from abnormal patella lateral tracking.

Reductions in strength and range of motion in older persons have been associated with decreased functional mobility and risk of falls. The purpose of this research was to investigate the effect of intensive dynamic balance exercise (DBE) during 8 weeks on onset time of medial gastrocnemius and tibialis anterior muscle contraction after perturbation in older women. Thirty subjects were randomly assigned into DBE group or control group. The DBE group participated in 50 minutes 3 days a week for 8 weeks. Surface electromyography (EMG) activity was recorded from the medial gastrocnemius and tibialis anterior muscles of left side. Outcome data were collected both groups at the pre-exercise and post-exercise. Independent t-test and paired t-test were used to determine the statistical difference. Results showed that the passive range of motion and functional reach test were significantly increased in the DBE group than the control group at the post-exercise (p<.05). The onset time of both muscles and discrepancy of onset time significantly reduced in the DBE group than the control group at the post-exercise (p<.05). The onset time of both muscles were significantly reduced in the post-exercise than the pre-exercise in the DBE group (p<.05). The discrepancy of onset time in the DBE group was significantly reduced in the post-exercise than the pre-exercise (p<.05). These findings suggest that intensive dynamic balance exercise for the eight weeks was effective in improving the postural control with older persons.

Purpose: This study was to verify the difference between reaction time of information processing and decision making information related with physical activity according to exercise self-schema. So it would have the hypothesis that exercise self-schema affected to judgement, remember and expectation of the content related with physical activity. Methods: The participants of experiment were 36(male:15, female21,Mage=21.25). Task was presented at computer screen. Participants reaction time and contents were saved automatically. And it was measured the physical activity’s amount for 7 days through questionnaire. All anaysis were conducted by SPSS 18.0 and AMOS 18. Results: It was shown that the participants who had higher exercise self-schema had faster information processing about physical activity content than the participants who had lower exercise self-schema. Also group of higher exercise self-schema had more vocabulary comments. And at the expect behavior related physical activity, the group of higher exercise-self schema seek more physical activity than the group of lower exercise self-schema. Finally, higher exercise self-schema group had more physical activity. Conclusion: it had identified that exercise self-schema was significant factor at information processing related physical activity. So it is needed to study and develop the program which help developing exercise self-schema.

본 연구는 대학생의 성, 학년, 운동변화단계에 따른 운동 자기-도식과 운동지속의사 그리고 주당운동시간을 확인하고, 남·녀 대학생의 주당운동시간에 운동변화단계, 운동 자기-도식 그리고 운동지속의사가 어떠한 영향을 미치는지를 확인하는데 그 목적이 있다. 이를 위해 대학생 404명(남자 197명, 여자 207명)에게 설문지를 실시하고, SPSS 18.0와 AMOS 18.0을 이용하여 문항분석, 변량분석, 신뢰도분석, 타당도분석, 상관분석, 회귀분석을 실시하였다. 그 결과, 성과 운동변화단계에 따라 운동 자기-도식과 운동 지속의사 그리고 주당운동시간이 유의미한 차이가 나타났다(p<.05). 그리고 주당운동시간에 영향을 미치는 요인을 확인하기 위한 단계적 회귀분석결과, 남성의 경우 주당운동시간을 예측하는 설명량은 43.6%이며, 여성의 경우는 37.8%로 나타났으며, 그 영향요인은 다소 차이가 보였다. 이와 같은 결과를 토대로 신체활동을 증가시키는데 운동 자기-도식의 형성이 중요함을 확인할 수 있었으며, 성차를 고려한 중재 전략이나 프로그램과 관련된 후속 연구가 지속되어야 할 것이다.

본 연구의 목적은 장기간 저항운동 강도별 스트레스를 지칭하는 호르몬의 분비 차이를 제시하는 것이며, 타 연구 논의의 차별화로 배제된 심리적 관련 변인을 기술하였다. 연구대상은 C 대학교 남자대학생 17명으로 최대하 및 최대운동 강도별로 각각 6주간의 저항운동 실시 후 네 시점별 성장호르몬과 테스토스테론 및 코르티솔의 차이 결과, 남성호르몬을 제외한 성장 및 코르티솔 변화는 안정시에 비해 운동직후 유의하게 증가하였으며, 6주 전후 변화는 코르티솔만이 네 시점별 유의한 증가가 있었다. 분비 차이의 의미로, 성장호르몬 증가는 운동 강도별 모두 유의하게 증가하였으며, 남성호르몬은 유의한 변화가 없었으며, 최대강도 운동의 경우 코르티솔은 6주 후 평소 안정 시에도 증가되어 있었다. 장기간 운동처치의 생리적인 결과 해석에 심리적 변화를 고려하여야 하며 부정적인 스트레스로 변환되지 않도록 심리적인 여러 변인 연구가 병행되어야 하겠다.