鄧茜 劉北湘
摘要:目的:探討振動(dòng)性伸展方式對足球運(yùn)動(dòng)員柔韌性及間歇性高強(qiáng)度沖刺的即時(shí)效應(yīng)。方法:以24名足球?qū)m?xiàng)運(yùn)動(dòng)員為對象,采用隨機(jī)交叉方式,分別在二周不同時(shí)段完成振動(dòng)式伸展、靜態(tài)伸展及控制處理。結(jié)果:振動(dòng)伸展組柔韌性顯著高于靜態(tài)伸展及控制組;振動(dòng)伸展組在6×10 s腳踏車間歇性沖刺中的功率峰值、平均功率、血乳酸濃度與運(yùn)動(dòng)強(qiáng)度感知(RPE)與靜伸組及控制組無差異;振動(dòng)伸展組在腳踏車間歇性沖刺中功率峰值出現(xiàn)時(shí)間明顯短于靜態(tài)伸展及控制組。結(jié)論:單次振動(dòng)式伸展有助于提升足球運(yùn)動(dòng)員柔韌性,并對改善運(yùn)動(dòng)員爆發(fā)力的動(dòng)作時(shí)間有益。
關(guān)鍵詞:靜態(tài)伸展;振動(dòng)伸展;熱身活動(dòng);間歇沖刺;足球運(yùn)動(dòng)員
中圖分類號:G804.6文獻(xiàn)標(biāo)識碼:A文章編號:1006-2076(2017)04-0058-06
Abstract:Objective: To explore the instant effects of different stretching on flexibility and intermittent high-intensity sprint in soccer player. Methods: 24 soccer-specific players were randomly assigned to vibrating, static, and control group and have been trained for 2 weeks in this study. Result: The flexibility in vibrated stretching was better than that in static and control group; the peak power, average power, blood lactate, and RPE of 6×10s sprint test on ergometer in vibrated stretching were no significant difference to that in static and control group; The duration of peak power of intermittent sprint in vibrated stretching was shorter than that in static and control group. Conclusion: The single session vibrated stretching has a good benefit on the flexibility of soccer players, and can improve the action time of power in players.
Key words:static stretching; dynamic stretching; warm-up exercise; intermittent sprinting; soccer player
前言
靜態(tài)伸展常被運(yùn)用在運(yùn)動(dòng)前熱身及運(yùn)動(dòng)后肌肉放松,其主要目的是預(yù)防運(yùn)動(dòng)傷害、增加柔韌性和提升個(gè)人運(yùn)動(dòng)表現(xiàn)等[1-2]。Williford等[3]則認(rèn)為可使用靜態(tài)伸展代替熱身活動(dòng),伸展部位包括腿后肌群、股四頭肌、足底肌肉和小腿肌。另有一些研究指出[4-5],靜態(tài)伸展雖可提升柔韌性,增加肌肉延展性,有益于預(yù)防運(yùn)動(dòng)傷害,但同時(shí)可能會(huì)短暫降低肌肉剛度(muscle stiffness),進(jìn)而造成肌肉收縮能力下降。振動(dòng)伸展是在原有靜態(tài)伸展基礎(chǔ)上介入振動(dòng)波的刺激,從而使人體肌纖維產(chǎn)生快速振動(dòng),由于振動(dòng)波能促進(jìn)肌肉中的肌梭敏感性或抑制高爾基腱器的活化程度,從而提升身體平衡感、強(qiáng)化肌力及增加骨質(zhì)密度等[8-9]。相關(guān)研究都支持[10-13]局部振動(dòng)伸展替代靜態(tài)伸展可以改變傳統(tǒng)訓(xùn)練觀念,達(dá)到提升柔韌性效果并可避免因肌肉過度拉長致使爆發(fā)力下降,且這種振動(dòng)介入的伸展模式還能使運(yùn)動(dòng)者在疼痛感較低的程度下,實(shí)施相同的柔韌性表現(xiàn)。
足球運(yùn)動(dòng)員在比賽規(guī)則允許范圍內(nèi)可采用奔跑、急停、轉(zhuǎn)身、倒地、跳躍、沖撞等動(dòng)作,這要求運(yùn)動(dòng)員要具備極好的柔韌性;另一方面,現(xiàn)代足球“高速度、強(qiáng)對抗”的特征則要求運(yùn)動(dòng)員必須具備承受大運(yùn)動(dòng)負(fù)荷的身體能力[12-15]。Spencer等研究發(fā)現(xiàn)[16],對于18歲的足球選手而言,6×30 m間歇性跑步?jīng)_刺表現(xiàn)與15 m沖刺時(shí)間、下蹲跳高度具有中度至高度的顯著相關(guān);Mendez等也發(fā)現(xiàn)[17],男性足球選手10×30 m間歇沖刺表現(xiàn)與10 m沖刺時(shí)間及20 m沖刺時(shí)間具有顯著相關(guān)性??梢?,間歇性高強(qiáng)度沖刺能力與單次爆發(fā)力具有一定程度的關(guān)聯(lián)性。黃馨葦?shù)韧瑯影l(fā)現(xiàn)[18],單次等長性半蹲式全身振動(dòng)運(yùn)動(dòng)(30 Hz,0.8 mm)有助于改善6×10 s腳踏車間歇沖刺后期的運(yùn)動(dòng)表現(xiàn)。查閱相關(guān)研究,目前關(guān)于全身振動(dòng)刺激介入對間歇性高強(qiáng)度沖刺表現(xiàn)的影響研究文獻(xiàn)有限,而從運(yùn)動(dòng)生化視角探討振動(dòng)介入靜態(tài)伸展對足球運(yùn)動(dòng)員柔韌性及間歇性高強(qiáng)度沖刺的瞬時(shí)表現(xiàn)的研究文獻(xiàn)更少,本研究希冀在這方面取得相應(yīng)的突破。
1研究對象與方法
1.1研究對象
以24名體育學(xué)院足球?qū)m?xiàng)的學(xué)生(年齡21.5±1.7歲;身高174.6±6.8 cm;體重68.8±7.5 kg)為受試對象,其運(yùn)動(dòng)等級均為二級及以上,訓(xùn)練年齡至少4年及以上。每位受試者在實(shí)驗(yàn)開始前需要了解研究目的、流程及可能發(fā)生的突發(fā)事件,并在自愿同意書上簽名。
1.2研究方法
1.2.1實(shí)驗(yàn)設(shè)計(jì)
1)以隨機(jī)交叉實(shí)驗(yàn)設(shè)計(jì),各項(xiàng)實(shí)驗(yàn)處理間隔時(shí)間在48 h以上。實(shí)驗(yàn)處理前所有受試者先腳踏車熱身2(功率設(shè)置50 W,轉(zhuǎn)速60 rpm),再以隨機(jī)交叉方式分別站在振動(dòng)平臺(產(chǎn)地:德國)上接受控制處理(簡稱控制組)、3組×2 min靜態(tài)伸展(簡稱靜伸組)和振動(dòng)式伸展(間稱振伸組)三種實(shí)驗(yàn)處理。每次實(shí)驗(yàn)處理后,立即執(zhí)行坐位體前屈測試,完后進(jìn)行6×10 s腳踏車間歇性沖刺測試,組間休息在踏車上,進(jìn)行動(dòng)態(tài)休息1 min(阻力設(shè)為0 kg)。
2)選取股二頭肌、股四頭肌和臀大肌作為伸展訓(xùn)練肌群。伸展股二頭肌方法為:讓受試者先站立于振動(dòng)平臺上,雙腳前后成一直線,雙膝伸直下顎內(nèi)縮,額頭盡量碰至脛骨,并將雙手輕放于振動(dòng)平臺上。伸展股四頭肌方法為:跪姿雙膝屈曲90度于振動(dòng)平臺上,伸展腳膝蓋向后約平行于非伸展腳1/2處,手抓伸展腳的腳背處,并將伸展腳的腳跟盡量碰至臀部。伸展臀大肌方法為:受試者采用坐姿于振動(dòng)平臺上,非伸展腳彎曲平貼于振動(dòng)平臺上,伸展腳跨過非伸展腳后踩于振動(dòng)平臺上,角度和振動(dòng)平臺垂直并扭轉(zhuǎn)上身(動(dòng)作示范見圖1)。
3)伸展姿勢順序?yàn)楣啥^肌的右腳至左腳,接著股四頭肌的右腳至左腳,最后臀大肌的右側(cè)至左側(cè),3個(gè)伸展姿勢左右相互對稱,共計(jì)6個(gè)伸展動(dòng)作。靜態(tài)伸展處理時(shí),采用振動(dòng)強(qiáng)度參數(shù)為0 Hz與0 mm,每個(gè)伸展動(dòng)作皆在振動(dòng)平臺上持續(xù)保持15 s;受試者5 s變換下一個(gè)伸展動(dòng)作,動(dòng)作交換均在振動(dòng)平臺上進(jìn)行。振動(dòng)式伸展組,采用振動(dòng)強(qiáng)度(25 Hz,2 mm),伸展姿勢及步驟皆與靜態(tài)伸展相同,而動(dòng)作交換均在振動(dòng)平臺持續(xù)振動(dòng)中進(jìn)行[14,16,18]。兩種實(shí)驗(yàn)處理中,受試者均于振動(dòng)平臺上進(jìn)行,每次3組,每組振動(dòng)120 s,組間休息60 s。[JP]
1.2.2測試方法
1)坐位體前屈。以坐位體前屈測量腿后肌群、臀部以及下背柔韌性。讓受試者坐在地上,雙腳伸直與肩同寬,腳跟頂住坐姿體前彎測量器兩邊,雙手重疊先深呼吸,吐氣同時(shí)雙手應(yīng)緩慢并盡可能向前延伸,過程中保持脊椎伸直且雙腳膝蓋盡量伸直,達(dá)最遠(yuǎn)處后約停2 s,以中指碰觸最遠(yuǎn)距離為準(zhǔn)[13,19]。每位受試者實(shí)施兩次檢測,取最高值進(jìn)行后續(xù)分析。
2)腳踏車間歇性沖刺。采納Lee研究方案[19]。此測驗(yàn)每組間隔休息1 min,每組沖刺10 s。測驗(yàn)開始前,受試者自行調(diào)整坐椅高度與手把位置。實(shí)驗(yàn)進(jìn)行中,給予受試者口頭鼓勵(lì)。研究所采用阻力負(fù)荷為受試者自身體重的7%[20],在6組測驗(yàn)中,組間給予1 min休息(采用動(dòng)態(tài)休息模式,即受試者持續(xù)騎腳踏車,阻力為0 kg)。6×10 s腳踏車間歇運(yùn)動(dòng)測驗(yàn)的功率遞減率計(jì)算如下:功率遞減率=[(每10 s平均功率的最高值-每10 s平均功率的最低值)/每10 s平均功率的最高值]×100%。
3)血乳酸濃度測驗(yàn)。采用血乳酸分析器(產(chǎn)地:日本)。使用前依操作手冊所列程序進(jìn)行。統(tǒng)一采集受試者左手食指的指尖血,檢測全血中的血乳酸值(采血量5 μL)。采血時(shí)間點(diǎn)為:安靜值(前測)、實(shí)驗(yàn)處理后、3×10 s腳踏車測驗(yàn)和沖刺后5 min,共計(jì)4次采集血樣。
4)運(yùn)動(dòng)強(qiáng)度自覺量表(rate of perceived exertion, RPE)。采用Borg(1982)的6-20運(yùn)動(dòng)強(qiáng)度自覺量表[21]評估全身感覺。檢測時(shí)間點(diǎn)為安靜值、實(shí)驗(yàn)處理后和腳踏車每次沖刺后。
1.2.3數(shù)理統(tǒng)計(jì)法
運(yùn)用SPSS17.0分析軟件,對柔韌性、6×10 s腳踏車間歇性沖刺測驗(yàn)所得功率遞減率進(jìn)行重復(fù)測量單因素方差分析;對6×10 s腳踏車間歇性沖刺測驗(yàn)的功率峰值、平均功率、達(dá)到功率峰值的時(shí)間、血乳酸值及RPE主觀感知強(qiáng)度等指標(biāo)采用重復(fù)測量雙因素方差分析法進(jìn)行處理。所有指標(biāo)的顯著水平設(shè)定為α=0.05。以Portney建議[22]為依據(jù),將效應(yīng)量臨界值定為:η2值在0.1以內(nèi)、0.11~0.20及0.2以上分別稱為小、中、大效應(yīng)量。
2研究結(jié)果
2.1柔韌性及功率特征分析
2.3運(yùn)動(dòng)強(qiáng)度主觀感覺分析
表2顯示:運(yùn)動(dòng)強(qiáng)度主觀感覺RPE值在實(shí)驗(yàn)處理方法及不同檢測時(shí)間無交互效應(yīng)(F=0.854, P>0.05,η2=0.091);主效應(yīng)不同實(shí)驗(yàn)處理方法間RPE亦不存在明顯差異(F=1.24,P>0.05,η2=0.081);主效應(yīng)不同檢測時(shí)間間RPE存在非常顯著差異(F=69.14,P<0.01,η2=0.855),均呈現(xiàn)出隨踏車沖刺組數(shù)的增多RPE值明顯增加,但S-N-K多重比較發(fā)現(xiàn),振伸組、靜伸組所獲子集組成員與控制組稍有差異。
3分析與討論
本研究發(fā)現(xiàn),在經(jīng)歷2 min腳踏車動(dòng)態(tài)熱身后,將振伸組(25 Hz,2 mm)作為運(yùn)動(dòng)前熱身活動(dòng)的一部分,確實(shí)能有效提升選手的柔韌性,其效果優(yōu)于靜態(tài)伸展與控制處理。相關(guān)研究報(bào)道[23-24],振動(dòng)伸展時(shí)維持在輕微不舒服的姿勢,伸展時(shí)間約10~30 s較可提升柔韌性。而本研究每個(gè)伸展動(dòng)作皆維持15 s,同樣獲得類似的訓(xùn)練效果。Kinser等[7,12]對體操運(yùn)動(dòng)員采用局部伸展動(dòng)作時(shí)發(fā)現(xiàn),局部振動(dòng)式伸展對提升柔韌性效果優(yōu)于靜態(tài)伸展,故振動(dòng)刺激作為熱身活動(dòng),不論采局部還是全身似乎都能達(dá)到較好柔韌性表現(xiàn)。
在隨后6×10 s間歇性高強(qiáng)度腳踏車沖刺測驗(yàn)中,本研究發(fā)現(xiàn):振伸組達(dá)到功率峰值時(shí)間要明顯短于靜伸展。這似乎可以說明,利用單次振動(dòng)伸展性刺激,有益于改善腳踏車沖刺的動(dòng)作時(shí)間,從而達(dá)到提升腳踏車間歇性沖刺的爆發(fā)力之目標(biāo)。黃馨葦?shù)萚18]將受試者分為控制組、無負(fù)重半蹲姿振動(dòng)組及負(fù)重式半蹲姿振動(dòng)組,結(jié)果發(fā)現(xiàn)功率峰值及平均功率兩項(xiàng)指標(biāo)中,無論有或無負(fù)重的振動(dòng)處理后,都有助于改善6×10 s間歇沖刺后半段高乳酸堆積時(shí)的爆發(fā)力運(yùn)動(dòng)表現(xiàn)。Ross等[25]研究證實(shí):振動(dòng)訓(xùn)練的快速反復(fù)刺激,可使Ia傳入神經(jīng)纖維釋放更多的神經(jīng)傳遞物質(zhì),改善神經(jīng)突觸的傳導(dǎo)效率,而張力性振動(dòng)反射(tonic vibration reflex, TVR)機(jī)制可以刺激神經(jīng)肌肉系統(tǒng),增加神經(jīng)反射,更加強(qiáng)肌肉的協(xié)調(diào)能力。
本研究的振伸組、靜伸組及控制組血乳酸值及運(yùn)動(dòng)強(qiáng)度感知RPE值沒有明顯差異,說明將振動(dòng)式伸展作為熱身手段是不會(huì)影響選手運(yùn)動(dòng)時(shí)的疲勞程度的。本研究結(jié)果中,在高強(qiáng)度腳踏車間歇沖刺時(shí),相較于靜態(tài)伸展處理而言,維持在高血乳酸濃度的情形下,振伸展組能更快達(dá)到功率峰值,這可肯定振動(dòng)式伸展介入熱身活動(dòng)確實(shí)能縮短選手在間歇性運(yùn)動(dòng)時(shí)至功率峰值的時(shí)間。Ritzmann等[26]學(xué)者指出,全身性振動(dòng)刺激具有誘發(fā)牽張反射的效果,這很可能是引起功率峰值時(shí)間縮短的原因之一,但目前依舊缺乏足夠的文獻(xiàn)支持,其真正機(jī)制有待于進(jìn)一步探討。但先前已有許多研究發(fā)現(xiàn)[27-31]采用急性靜態(tài)伸展對選手爆發(fā)力表現(xiàn)會(huì)造成負(fù)面影響,而本次研究卻并未發(fā)現(xiàn)靜態(tài)伸展不利于間歇性高強(qiáng)度沖刺的爆發(fā)力表現(xiàn),此與先前研究存在差異,導(dǎo)致這種差異的原因可能是伸展時(shí)間與組數(shù)不同所致。如Beckett[27]采用6個(gè)伸展部位連續(xù)伸展20 s,而本研究伸展的部位是下肢三處大肌群(時(shí)間15 s、組數(shù)3組);Behm[1,5] 等認(rèn)為伸展強(qiáng)度維持在輕微不舒服的狀態(tài),但伸展持續(xù)時(shí)間應(yīng)少于90 s,如此能降低伸展所引起的負(fù)面效應(yīng)。
4結(jié)論
振動(dòng)式伸展(頻率25 Hz,振幅2 mm)對足球運(yùn)動(dòng)員柔韌性有明顯促進(jìn)作用,且效果顯著優(yōu)于靜態(tài)伸展處理組和控制處理組;振動(dòng)式伸展可減少間歇性高強(qiáng)度沖刺至功率峰值輸出的時(shí)間,這對改善運(yùn)動(dòng)員爆發(fā)力的動(dòng)作時(shí)間是有益的;振動(dòng)式伸展不會(huì)增加間歇性高強(qiáng)度沖刺血乳酸值及運(yùn)動(dòng)強(qiáng)度感知RPE值,因而不會(huì)增加選手運(yùn)動(dòng)時(shí)的疲勞程度。
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