腰椎屈曲度（下） | Lumbar Spine Flexion

腰椎屈曲度（下） | Lumbar Spine Flexion

 

腰椎屈曲度

該如何避免脊柱完全屈曲？

雖然避免脊柱最大屈曲有可能降低受傷風險，但適度屈曲（最大屈曲的60%-80%）可以提高運動表現，同時促進脊柱的最佳負荷分配。因此，我們可以提醒運動員或自己在進行大重量動作時，保持ROM在生理限度內的脊柱對齊。一般來說，允許腰椎彎曲到呈現直線的點可產生適度彎曲，同時避免腰椎的後凸姿勢來到ROM的生理限度位置。因此，適度地進行動作提示會是很重要的預防方式。例如在進行負重下蹲時，為了避免脊柱末端屈曲，可以進行提示如”動作時避免下背變圓”和”保持脊柱拱形（弓背）”。透過適當提示可有效地減少過程中的腰椎屈曲。我們應使用阻止過多的脊柱動作和提升下肢降低眾信的提示，來幫助每位運動員降低受傷風險及提高表現。

 

當然我們也可以透過觸覺反饋來提升運動員自身的本體感覺意識，預防在舉重練習期間發生末端ROM屈曲。可以進行的預防方式如在脊柱平行縱向放置PVC管或是使用貼紮保護脊柱末端，以便運動員在髖絞鍊及下蹲練習終接近末端ROM屈曲時得到反饋。在大多數情況，只需使用一至兩次課程時間，即能夠產生相當持久的效果。此外，運動的選擇會對於脊柱位置產生極大的影響，特別對，於活動範圍有所限制的個體來說。例如進行抓舉上拉時需要大量的髖關節屈曲，對於缺乏髖關節活動度的運動個體而言，將可能促使相連關節節段的代償。在這個例子當中，進行腰椎屈曲會是當髖關節活動受限，將雙手降低碰觸槓鈴的常用策略。

 

使用輔助器材來增加ROM也是一種方式，我們可以使用這種策略來控制脊柱彎曲。對於活動度受限的運動個體，我們可以使用腳底墊塊或放置小槓片來幫助下蹲於平行位置以幫助避免脊柱屈曲末端。隨著負重動作時的脊柱屈曲度逐漸增加，減少舉重訓練時的ROM會減少脊柱彎曲程度。因此，教練在決定動作的ROM上限時，必須要考慮運動員對於控制脊柱後凸姿勢的能力。最後，當我們想要進行全範圍活動如全蹲時，踝關節與髖關節掌握足夠活動度對於避免脊柱末端屈曲是相當重要的。舉例來說當踝關節背屈ROM受限時，將會限制膝蓋向前位移的能力，連帶導致骨盆相對於向下支撐點的向後移動。軀幹會過度前傾為保持平衡，在此情況下脊柱屈曲度將難以避免。同樣地當髖關節活動度受限時，下蹲時將可能產生骨盆過早後傾，進而增加了脊柱屈曲。

 

進行保護脊柱的訓練

脊柱本身非常堅固，能夠在各種不同的姿勢下承受極高負荷。在全ROM負荷訓練中，腰椎屈曲幾乎是不可避免的事情，且這也有可能利於提高動作表現。不過，以腰椎最大程度彎曲進行動作可能會有更大的受傷風險，因為脊柱抗壓強度受到損害，且會讓椎間盤和後韌帶受到壓力/甚至損傷。

我們可以透過指導動作的協調模式來優化脊柱負荷分擔能力，且將運動個體身體素質考慮進練習當中來培養運動所需技能，將能避免過度腰椎屈曲。在適當的條件下再輔以靈活度訓練，以幫助運動員在舉重訓練中能夠降低重心的能力。

 

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參考自：simplifaster.com