Published papers

Resistance training with whole-body vibration (WBV) is becoming increasingly popular as an alternative to conventional resistance training or as supplementary training. Despite its growing popularity, the specific effects of WBV training on muscle morphology, strength, and endurance are not well understood, particularly in young adults. The aim of this study was to determine the effects of WBV training on bone-free lean body mass (BFLBM), and maximal muscle strength and endurance in healthy, untrained, young individuals. Eighteen healthy men and women (21-39 years) were randomly assigned to either a body-weight exercise with WBV (VT) group or a control exercise group without WBV (CON). Participants performed eight exercises per 40- min session on a vibration platform (VT group, frequency = 30-40 Hz; amplitude = 2 mm) twice weekly for 12 weeks. Anthropometry, total and regional BFLBM (trunks, legs, and arms) measured by dual- energy X-ray absorptiometry, and muscle strength and endurance measured by maximal isometric lumbar extension strength, maximal isokinetic knee extension and flexion strength, and the number of sit- ups performed were recorded and compared. Two-way repeated-measures ANOVA revealed no significant changes between the groups in any of the measured variables. We conclude that 12 weeks of body weight vibration exercise compared to body weight exercise alone does not provide meaningful changes to BFLBM or muscle performance in healthy young adults. Key pointsA randomized controlled trial was conducted to investigate the effects of body-weight exercise combined with whole-body vibration on bone-free lean body mass and maximal muscle strength and endurance in healthy young individuals.Body-weight exercises for lower extremities and trunk muscles were performed twice weekly for 12 weeks.Participants in the exercise with whole-body vibration group increased the vibration frequency from 30, 35, to 40 Hz at a constant amplitude of 2 mm during the trial.A 12-week body-weight exercise program with whole-body vibration did not significantly increase bone-free lean body mass in healthy young individuals, and no additional increases in maximal muscle strength and endurance were observed.

Although resistance training (RT) combined with whole-body vibration (WBV) is becoming increasingly popular among untrained adults, the additional effects of WBV on muscle fitness are still not well understood. The aim of the present study was to evaluate the effects of WBV on muscle strength, muscle power, muscle endurance, and neuromuscular activities compared with the identical RT without WBV. Thirty-three individuals (6 males and 27 females; 22-49 years old) were randomly assigned to a training program using slow-velocity RT coupled with WBV (RT- WBV group, n = 17) or an identical exercise program without WBV (RT group, n = 16). Participants performed eight exercises per 60 min session on a vibration platform (RT-WBV group, frequency, 35 Hz; amplitude, 2 mm) twice weekly for seven weeks. To evaluate the effects of WBV, the maximal isometric and isokinetic knee extension strength, maximal isometric lumbar extension strength, countermovement-jump, and the number of sit-ups were measured before and after the trial. Significantly higher increases were observed in the maximal isometric and concentric knee extension strength (p = 0.02, p = 0.04 , respectively), and maximal isometric lumbar extension strength at 60 degrees of trunk flexion (p = 0.02) in the RT-WBV group (+36.8%, +38.4%, +26.4%, respectively) in comparison to the RT group (+16.5%, +12.8%, +14.3%, respectively). A significant difference was also observed between the RT-WBV group (+8.4%) and the RT group (+4.7%) in the countermovement jump height (p = 0.02). In conclusion, the results suggest that significant additional increases in maximal isometric and concentric knee extension and lumbar extension strength, and countermovement jump height can be achieved by incorporating WBV into a slow-velocity RT program during the initial stage of regular RT in untrained healthy adults. Key pointsA randomized controlled trial was conducted to investigate the effects of slow velocity resistance training combined with whole-body vibration on maximal muscle strength, power, muscle endurance, and neuromuscular activities in healthy untrained individuals.Resistance training program for lower extremities and trunk muscles were performed twice weekly for 7 weeks.A 7 weeks slow velocity resistance training program with whole-body vibration significantly increased maximal isometric knee extension and lumbar extension strength and power in healthy untrained individuals.

健康的な生活習慣定着、QOL向上のためのインターネット・地域連携健康支援システムの構築を行った。ウェブ上での健康支援システムとして、食事記録システム、生活習慣・健康状態アセスメントシステムを開発し、藤沢市のシニアNPOなどの協力を得て13名(男8名、女5名、平均64.7歳)を対象に試用した。「ふれあい健康教室」を開催し、インターネット・地域連携コミュニティーの醸成を図った。藤沢市、藤沢市保健医療センター、大学とで健康増進システム作りのための定期的会議を行った。また、運動を行う上でハイリスクとなる参加者を同センターに紹介し、ヘルスチェックを受ける体制を試行し、平成22年度はハイリスク者4名のうち2名がセンターを受診した。

藤沢市で2009年に特定健診を受けた40〜69歳の国保被保険者の中から無作為抽出した4165名に質問紙調査を行い、活動的な移動手段としての歩行・自転車利用と環境要因との関係、メタボリックシンドローム(MeS)と環境要因との関係などについて検討した。2449名から回答が得られ、性別は男性1194名、女性1255名であった。検討の結果、活動的な移動手段としての歩行時間と有意な関連を示す環境要因として男女とも「住宅密度が高いこと」「近所にスーパーや商店があること」「歩道があること」「自動車・オートバイを所有していないこと」が抽出され、女性では「近所に運動場所があること」「近所で運動実施者を見かけること」も抽出された。自転車利用と有意な関連を示す環境要因は男女とも「自転車運転時の安全性(交通量)」が抽出され、男性では「近所に自転車道があること」「運動場所があること」「近所で運動実施者を見かけること」、女性では「自動車・オートバイを所有していないこと」も抽出された。MeS非該当に関連する環境要因として、男性で「自動車・オートバイを所有していないこと」、女性で「近所に自転車道があること」「近所で運動実施者を見かけること」「近所の景観が良いこと」が抽出された。

65歳以上の高齢者への「運動」介入が運動器の機能に関連するアウトカム改善に効果があるか否かについて、システマティックレビューを用いて検証した。高齢者に対する虚弱改善や介護予防において最も重要と考えたアウトカムであるADL、IADLを、運動介入によって改善させるか否かという視点では、効果を肯定的に示した文献数が少なく、一定の知見を得ることは困難と考えられた。しかし代理アウトカムでは、複合的な運動トレーニングにより転倒を減少させ得ること、十分な強度の筋力トレーニングであれば骨格筋量を増加させ得ること、特定の種目でなくとも十分な強度・頻度の運動介入により高齢者の膝痛の軽減が期待できること、が示唆された。(著者抄録)

Exogenous stimulation of skeletal muscle or tendon is often used to improve range of motion. Despite substantial research efforts, however, the effects of vibration on flexibility have not been clarified. In this review, we investigated the effects of acute and chronic intervention programs which used vibration to improve flexibility in young healthy individuals. Effect size was calculated using data from a total of 600 participants in 19 studies before and after the introduction of vibration-based intervention, and a total of 324 participants in 13 studies on the additive effects of vibration compared with the identical conditions without vibration. Sub-group analyses were performed based on intervention period, type of exercise, and type of vibration. Meta-analysis showed that vibration interventions had significant effects on flexibility (standardized mean difference [SMD]=-0.79, 95% confidence interval [CI]=-1.14- -0.43; p<0.001), albeit with the possibility of heterogeneity (I(2)=75%). Another meta-analysis revealed a significant additive effect of vibration on flexibility compared with the identical condition without vibration (SMD=0.25, 95%CI=0.03-0.48; P=0.03), with small heterogeneity (I(2)=0%). The risk of publication bias was low judged from Kendall's tau statistic. We concluded that the use of vibration might lead to additive improvements in flexibility.

Exercise with whole-body vibration (WBV) is becoming popular as an alternative to conventional training or as supplementary training. However, despite increasing research efforts in this field, additive effects of WBV on muscle performance remain unclarified. In this review, we investigated the additive effects of long-term WBV on muscle strength and power. This meta-analysis was restricted to randomized controlled trials lasting for at least 5 weeks comparing exercise with and without WBV, or comparing only WBV exposure and control. Data from a total of 314 participants in 10 studies on knee extension muscle strength, and 249 participants in 7 studies on countermovement jump height were pooled using random-effect models. Meta-analysis showed significant additional effects of WBV on muscle strength (standardized mean difference [SMD]=0.76, 95% confidence interval [CI]=0.21-1.32; p=0.007) and countermovement jump (SMD=0.87, 95% CI=0.29-1.46; p=0.003). Based on these findings, we concluded that the use of WBV would lead to greater improvements in both knee extension muscle strength and countermovement jump than under identical conditions without WBV.

Recent studies have suggested the importance of the neighborhood environment in determining the specific type of physical activity. However, few studies on this topic have been undertaken in Japan. This study examined the association of three types of physical activity and their associations with individual and neighborhood environmental factors among middle-aged and elderly Japanese. Participants were 2,449 adults aged 40-69 living in Fujisawa city who had undergone health checkups and responded to our survey by mail. Individual factors, the International Physical Activity Questionnaire (long form), and its environmental module acted as inputs to the study. The adjusted odds ratios (ORs) of high levels of moderate-to-vigorous intensity leisure-time physical activity (LTPA), walking for active recreation, and transportation were calculated in relation to individual and neighborhood environmental factors through multiple logistic regression models. Not working and good self-rated health were significantly associated with a higher level of each physical activity outcome. According to the adjusted ORs, higher educational attainment, higher economic status, good access to exercise facilities, and owning motor vehicles were associated with longer LTPA time. However, different sets of factors were associated with longer walking times for recreation and transportation. The results suggest that diverse individual and neighborhood environmental characteristics are associated with different physical activity outcomes. Therefore, customizing environments to become activity-friendly is necessary to increase physical activity effectively among middle-aged and elderly Japanese.