一個高價值訓練動作——後腿抬高分腿蹲的技術動作、變式、以及進階

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三個導讀內容

1）RFESS：

rear-foot-elevated split squat

後腿抬高的分腿蹲

2）紅字部分為個人解讀

3）人體位面圖，三個面的意思，下文會有描述，大略明白一下指的是什麼

個人認為該動作的意義：

1）促使下肢各關節在正確的排列下，發展出平衡穩定的功能性力量，有積極的康復意義。

2）平衡身體左右兩側的肌肉不均衡，減少雙邊偏差，可作為雙側傳統訓練動作的補充訓練，提高全面運動表現。

3）通過身體角度與負重道具的適當調整，對於臀部肌肥大有非常大的意義。

4）修復身體在執行雙側動作時，由於關節功能不足而代償所導致的慢性疼痛（下背部、膝蓋）。

介紹

RFESS和單腿深蹲、分腿箭步蹲的差異與相同點

相同點：

     在矢狀面（身體前後平面）都有關節的屈伸運動（蹲起下落），同時由於單腳模式使得身體更不穩定，需要身體額狀面與水平面更多的穩定性（對抗向左向右傾倒；對抗向左向右轉）

不同點：

     RFESS相較於箭步蹲來說，對單側下肢的刺激更大（RFESS85%;箭步蹲75%）

     儘管這個動作一開始很難掌握（比較深蹲而言），但是可以通過不同的變式去增減難度，從而使得身體逐漸能夠掌握它。如果你想練習單腿深蹲的話，也可以先以RFESS作為鋪墊，它能幫助你建立一定的單腿力量與穩定基礎。

     REFESS不僅適用於單側下肢最大力量的測試，也可以使用不同的次數去練習，同時由於RFESS對下肢的穩定性提出了更高的要求，也可以放入你的核心訓練計劃中，讓你可以更好地完成傳統雙側動作（深蹲硬拉）。

（在任何雙側動作中，尤其是接近一個自己無法控制的重量時，身體會出現左右的不平衡。這是由於你左右兩側身體單側的力量不平衡導致，這種不平衡是永遠客觀存在的，在力量訓練中，會在你疲勞時出現，影響你的進步，甚至導致受傷。因此單側的下蹲動作RFESS可以非常好地作為傳統雙側力量訓練的輔助訓練，這個話題在以往的文章中有提到過）

     鑑於幾乎所有體育運動的動作特點，如加速、減速、變相、衝刺、跳躍等都是需要人體下肢複合關節，在一定壓力下產生力量，並且向身體遠端（上方）傳導，可見REFSS對於增強身體運動功能方面的收益是非常高的，尤其是通過對髖關節功能的強化，使全身運動系統（包括正確的膝蓋、足部姿勢）更加穩定強健（髖關節也就是屁股，人體的中心，串聯上下肢功能）

箭步蹲

單腿深蹲

涉及的肌肉

矢狀面：臀大肌、膕繩肌、股四頭肌

額狀面：臀中肌、臀小肌、闊筋膜張肌（用於防止身體側傾與旋轉）

水平面：髖部負責外旋與內旋的肌群（主要通過穩定支撐側髖關節，使其保持一定外旋角度，同時穩定後側髖關節，使其保持一定內旋角度，這兩方面防止身體左右旋轉）

     同時較不穩定的接觸面（單腳），會激活足底穩定肌群（腓腸肌、比目魚肌、脛骨前肌、脛骨後肌、腓骨長短肌），以及維持軀幹穩定的腹斜肌以和豎脊肌群

（這種穩定性的刺激需求，對於因喪失足底穩定而受傷的訓練者，有康復意義）

訓練技巧詳解

1）支撐腳腳趾與後腳支撐平臺的距離大約是一條腿的長度，並在前支撐腿腳趾的位置在地上做一個記號。（原文是髂嵴與地面的高度，近似腿長吧，可以自行調整至舒服的位置）如果距離過長可能會導致身體過度前傾，不利於槓鈴負重於頸後的單腿蹲形式（頸後的負重模式需要脊柱儘可能直立）。

2）先在無負重的前提下進行動作練習，確保動作過程中，膝蓋朝向腳尖且足底穩定（足踝詳細內容可見上一篇文章）腳尖的方向指向前方。（前方具體是哪裡？無論是Mike boyle的功能性訓練還是本文都沒有指出，個人多年的實踐經驗與觀察得出，向前並且稍微向內一點點。正確朝向的肌肉感覺，是整個下肢腿部、臀部360度都會發力。如果沒有這一點向內的話，大腿內側的肌群將不會被激活，但是過度向內可能造成膝內扣）

3）後腿支撐平臺的高度範圍推薦可從15cm到與膝同高的範圍

4）如果使用較大負荷的槓鈴放置於頸後執行動作，需要有保護人員在身體兩側以及後側，啞鈴就不太需要，可以直接放地上。

5）動作開始應該先手持、肩扛負重前後分腿站在支撐平臺前面，把前腳放在指定的標記地點，轉移重心至前腳，然後穩定地把後腳抬高放在平臺上。

6）後腳與支撐平臺的接觸位置，應該在腳背或者腳背與腳趾連接處，不要用腳底支撐，否則會增加穩定性，從而降低動作難度。

7）前後腳的左右寬距大約與髖關節同寬即可。

8）維持整個動作過程中軀幹的挺直，儘量不要俯身（個人解讀：如果是槓鈴在頸後的負重模式，確實需要如此，就和頸後深蹲一樣。但是如果用啞鈴放在體側作為負重的話，適當的俯身增加髖屈角度，可以增加身體後側鏈的參與，尤其對於臀部的刺激非常大）

9）將重心保持在前腳足底中部或者靠近腳根（個人解讀：切忌不要完全在腳根，因為重心如果在腳根的話，容易給後腿過多壓力，而此時後腿處於一個不合適的發力環境。除此之外，稍微偏向腳根，配合適當的俯身幅度，類似於單腿硬拉，有利臀部的刺激）

10）注意從側面觀察，啞鈴或者槓鈴在動作過程中應該要直上直下（可以叫別人幫忙看，或者自己手機錄像）

進階動作與變式

自重的地面箭步蹲

側重大腿前側

側重臀部（忽略啞鈴）

用懸掛裝置進行輔助完成RFESS

依靠上肢輕微借力完成動作（注意看頭部的姿勢與整個後背的姿勢）

自重RFESS

史密斯RPESS

史密斯機空杆的穩定負重軌道可以減少身體的穩定需求，降低動作難度。（配合略微俯身的角度，對於臀部的刺激非常大）

用啞鈴／壺鈴放置於身體體側進行負重

姑且用鮑爺這本書的封面作例子，沒看過的可以看一看。動作過程中需要對啞鈴的有穩定的垂直軌跡控制

（個人解讀：實際上在Mike boyle的訓練體系中，會先進行啞鈴的胸前負重，直至最重，再換成雙邊負重。胸前單邊負重無疑會更佳穩定一些，但是要注意做的時候啞鈴全程貼緊胸口，意思就是身體儘可能不要俯身，否則啞鈴便會離開身體。在個人長期自我實踐與教學實踐中發現，直接做雙側負重也是可行的）

槓鈴頸後負重的RFESS

可以有很高的負重潛力，但是由於負重的重心變高，使得身體維持姿勢的難度增加，脊柱各個角度的扭矩也增加，因此動作難度大大增加，需要有保護者在旁邊。

RFESS變式

用於增強下肢穩定性：

將後腳放在懸掛繩上進行RFESS，最大程度減少後腿發力，對單腿的穩定性提出極高的要求

用於改善肌肉不平衡與雙邊偏差，優化單、雙側動作：

如果右腳是支撐腳，那用左手進行單邊負重，會對右邊髖部外展肌群以及身體單側核心提出更高的要求。

（個人解讀：可以看作是膝關節內扣、足弓塌陷無力、軀幹旋轉等一系列代償動作的整體解決思路，因為這些所有的問題是綜合影響身體姿勢的，那就應該用綜合的動作去解決，而不是只是孤立地進行拉伸某一邊緊張的肌肉，並且只做一些雙側訓練）

常見錯誤

1）前腿膝蓋沒有朝向正確的腳尖位置

（個人解讀：這個現象的本質其實是足底穩定不足，髖關節周圍肌力不平衡，可解決的訓練層面上的策略，可以是上文提到的單邊負載的變式）

2）身體過度前傾，支撐腳腳背沒有放平

（與上篇文章一樣，在頸後負重模式的動作中，無論是單腿還是雙腿，最好保持脊柱儘量垂直於水平面，減少俯身角度，而如果是自重、啞鈴體側甚至是史密斯負重形式的RPESS，在穩定控制的原則下，可以適當俯身，增加臀部刺激）

3）支撐平臺的高度不能太高

具體情況因人而異，一般來說膝蓋的高度比較合適

4）膝蓋超過腳尖太多，導致腳根抬起；膝蓋前移太少，導致小腿幾乎垂直於地面。

（前者會造成不必要的膝蓋壓力（特殊健美式股四頭肌訓練法例外），後者會給後腿帶來不必要的壓力）

5）前後腳的左右距離太窄從而導致下肢不穩定性增加，使得身體歪斜

（當然反過來，也可以通過減少這個距離，增加不穩定性，增加訓練難度）

實際應用

     

     RFESS訓練，將下肢放置於一個有挑戰性又接近於實際生活與運動的姿勢當中（單腿），這種形式的訓練能夠增加整體下肢的穩定性、與功能性力量，修正過度活躍的髖內收肌群及其帶來的整個身體的代償，修正單側偏差，優化雙側運動模式，降低膝蓋、腳踝、與髖關節的潛在受傷風險。這種由於臀部力量較弱，髖關節過度內收（膝蓋內扣），足底向內塌陷的不平衡力學姿勢在女性身上尤為常見，在力量訓練中這種偏差姿勢將可能帶來受傷的風險。

原文

INTRODUCTION

The rear-foot-elevated split squat (RFESS) is similar to the single-leg squat, lunge, and split squat but also varies from each. Although all these exercises include flexion and extension predominantly in the sagittal plane, the narrow base common to these exercises introduces the demand for frontal plane control. The anterior-posterior stance also includes rotation in the hips that occurs in the transverse plane. Unique to the RFESS is significantly reducing the support of the load on the trail leg by placing the top of the foot on a raised supporting device. The lead leg has been shown to support approximately 85% of the load (6), which is greater than the split squat and lunge (75%) (4). Many modifications of the exercise can be performed to fit the beginner to advanced lifters. With added support from the trail leg, the exercise can be used as a progression before the single-leg squat when the exercise is performed with just the bodyweight or light dumbbells. This added support of the trail leg can also be used to increase the loads for lifters at various levels of experience.

Because of the level of instability present, the exercise can be used for joint stabilization; however, the RFESS can be included in the program design as a core exercise similar to the emphasis placed on other types of traditional, multijoint, lower-body exercises. Strength assessment can take place using 1 repetition maximum (1RM) loads as well as rep tests using various RM loads (5). For those without previous training using the RFESS but have resistance training experience, a practice session and pretest is suggested before a final assessment of strength to eliminate any possible learning effect. Heavy relative loads recommended to increase strength during training can also be used (5).

Although most ground reaction forces in sport are produced from a unilateral stance, the RFESS can be used for improvement in a wide variety of sports. Acceleration, deceleration, change of direction, sprinting at top speed, and jump performance all require stability of the lower extremity joints under loaded conditions to produce forces through the kinetic chain for efficient movement. The RFESS particularly trains the hip to support the upper body while also controlling the knee position in the unilateral stance.

MUSCLES INVOLVED

The hip (gluteus maximus and hamstrings) and knee extensors (quadriceps) are active in the sagittal plane (6). For frontal plane control and prevention of a lateral pelvic tilt, the hip abductors are required (gluteus medius, gluteus minimus, and tensor fascia latte) (6). Internal and external hip rotators maintain the degree of external rotation of the lead hip and internal rotation of the trail hip. The reduced base of support also activates the plantar flexors (gastrocnemius and soleus), inverters (anterior and posterior tibialis), and everters (peroneals). The active trunk musculature includes primarily the obliques and extensors (erector spinae and multifidus).

EXERCISE TECHNIQUE

• Place a mark on the floor to position the lead toe line.

• The distance from the lead foot toe line to the trail foot support is approximately the length of the iliac crest to the floor.

• Without added load, practice the RFESS to adjust the support box/bench distance that allows the lead knee to be positioned directly above the toe line. Tight hip flexors can create excessive forward lean of the torso to reach the pad with the trail leg, which may require reducing the distance of the support device.

• The trail leg support can range from approximately 6 inches to knee height.

• When using a free-weight bar and heavy relative loads for strength improvement, the exercise should be performed inside a squat rack with spotters positioned on both sides and 1 positioned behind the lifter. With dumbbells and lighter loads, spotters may not be necessary.

• After placing the bar on the shoulders or dumbbells in the hand, place the lead leg toe line on the mark then take a split squat stance with the trail leg just in front of the support device and the foot still on the floor. While shifting the weight toward the lead foot, place the top of the trail foot on the support pad.

• Positioning the trail ankle in slight to complete plantar flexion reduces instability of the exercise.

• Contact between the trail foot and support device should be on the metatarsals or the metatarsophalangeal joint.

• The stance width between the lead and trail foot should be approximately hip width.

• Maintain a near vertical torso in the starting position and throughout the movement. A forward lean (hip flexion), similar to the bilateral squat, is difficult to control with the split stance and rear foot elevated.

• Keep the weight of the lead foot distributed in the middle of the foot or near the heel.

• The bar should track in a vertical line during the descending and ascending phases. Instruct the lifter to sit straight down to improve bar path.

• The lead knee should track in line with the foot that is pointed forward.

• Bring the trail knee down until it touches a 1-2-inch foam pad placed on the floor.

• Complete the repetitions in the set before switching legs.

PROGRESSION AND VARIATIONS

• Bodyweight holding suspension bands (Figure 1).

• Smith machine—the stabilized load significantly reduces muscle activation in the frontal plane.

• Bodyweight—for untrained lifters, the weight of the body can provide an overload.

• Bodyweight split squat.

• Bodyweight with the trail leg supported with a suspension band (Figure 2). After placing the trail foot in the strap, you may need to hold onto the safety bars to position the lead leg on the mark.

• Dumbbells with a stable trail leg support—the dumbbells lower the center of mass which can improve the stability of the exercise. The lifter can set the dumbbells on a bench positioned on each side and elevated approximately knee height before performing the exercise. Once in position with the trail foot supported, the lifter can lift the dumbbells to begin.

• Unequal dumbbell—to increase the frontal plane overload on the lead leg, use a heavier dumbbell on the trail leg side. A dumbbell could be used on the trail leg side without one on the lead leg side to further increase the lateral pelvic tilt torque. With dumbbells of equal load held in each hand, the dumbbell on the lead leg side counterbalances a portion of the load creating the lateral pelvic tilt. For example, a 20-lb dumbbell held on the trail leg side creates more frontal plane torque toward that side than a 20-lb dumbbell held in each hand. This unilateral load creates more demand from the hip abductors and other musculature for frontal plane support (7). Variations of the load in each hand can be used to independently control the overload in the sagittal and frontal planes (Figure 3).

• Barbell on the shoulders—progression of loads can occur for strength training. Strength improvement has been found with progression up to 87% of 1RM loads performed for 6 repetitions during short-term training (5). The high center of mass increases the difficulty in maintaining the posture and in recovering from any angular motion of the torso due to the increase in torque (Figure 4); therefore, spotters are warranted.

COMMON ERRORS

• Lead knee not directly above the lead toe line (Figure 5). Although it is acceptable to have the knee slightly in front of the toe line, a knee position well behind the toe line with a vertical tibia places too much load on the trail leg.

• Excessive torso deviation from vertical (Figure 5). A forward leaning position is possible with bodyweight but is not recommended with the bar on the shoulders. Cue the lifter to stand tall with a vertical torso.

• Inaccurate trail foot support distance—before adding load, practice the technique to adjust the distance that allows a vertical torso and lead knee directly over the lead toe line.

• Trail foot support height. This can vary based on leg length and flexibility, but near knee height is recommended.

• Supporting the ankle/tibia of the trail leg on the support pad. Allows for more weight to be distributed to the trail leg. The lifter can shift more load to the trail leg resulting in the bar tracking posterior from vertical.

• Neutral or dorsiflexion in the trail ankle resulting in contacting the support device on the tip of the toes (Figure 5). A plantar-flexed position improves the stability of trail leg support.

• Excessive hip adduction/lateral pelvic tilt, which makes it difficult to control the resistance in the frontal plane (Figure 6).

• Increased knee valgus (Figure 6).

• Stance not hip width—a trail foot positioned directly in line with the front foot may be difficult to control the load in the frontal plane leading to increased lateral pelvic tilt.

PRACTICAL APPLICATION

The RFESS has the potential to reduce the risk of hip and knee injuries. Frontal plane stabilization of the hip enhances muscular control of hip adduction in the stance leg (3). Repetitive excessive hip adduction/lateral pelvic tilt on the support leg during gait could lead to chronic soft tissue disorders of the hip and knee (2). Hip adduction can also lead to anterior cruciate ligament stress because of an increase in knee valgus (1). This is a common occurrence during unilateral, weight-bearing activities, particularly in female athletes (8). Hip weakness in a unilateral stance can be assessed in clients with various levels of ability. For untrained and individuals with low levels of strength, the ability to maintain a level pelvis can be observed in a stationary unilateral stance (Trendelenburg's sign). To progress the assessment, a single-leg squat and jump landings can also be used to observe lateral pelvic tilting and the degree of knee valgus. Training with the RFESS can be used to provide improved trunk and lower-body joint stabilization mediated primarily by the hip musculature during unilateral based activities. Using the progression of the RFESS provided, the strength and conditioning specialist can assign an appropriate level of exercise that allows correct technique to be performed while monitoring the noted errors and providing corrective feedback.

Performance in a wide range of sports involving lower-body, weight-bearing skills occurs primarily under unilateral conditions. In addition to sprinting and change of direction, throwing, kicking, and striking patterns require the transfer of forces unilaterally that need to be simulated during training. With the majority of the resistance placed on the lead leg, the RFESS can be implemented in a resistance training program to increase strength of the lower body while achieving sport specificity. Although the exercise includes some degree of instability, loads recommended for improved muscle mass, strength, and power can be used to provide the necessary overload. To obtain maximum benefits, following proper technique and progression guidelines is essential during training with the RFESS.

REFERENCES

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