แปลไทยสั้นๆคือ หลายคนยังกลัวว่าการลงสุดในท่า Squat ( Deep Squat ) นั้นอันตรายต่อข้อต่อและเอ็นหัวเข่ามาก แต่สรุปแล้วจาก Study คือ กลับกันเลย ยิ่งลึกยิ่งปลอดภัยกว่ามาก ช่วงที่อันตรายต่อข้อต่อและเอ็นหัวเข่ามากที่สุดคือช่วงระยะ 4 นิ้วแรกที่เริ่มหย่อนตัวลง Squat ต่างหาก อีกอย่างที่อันตรายคือ Squat ท่าพิสดารเช่น เข่าบิด
Some people are still under the impression that deep squats place excessive stress on the ligaments of the knee (especially the ACL). However, it appears these concerns are not based in science at all.
Science now tells us that the ligaments inside our knee are actually placed under very little stress in the bottom of a deep squat. The ACL (anterior cruciate ligament) is the most well known ligament of the knee. ACL injuries are common in popular American sports such as football, basketball, soccer, lacrosse, etc.
The stress to the ACL during a squat is actually highest during the first 4 inches of the squat descent (when the knee is bent around 15-30°). As depth increases the forces placed on the ACL significantly decrease. In fact, the highest forces ever measured on the ACL during a squat has only been found to be around 25% of its ultimate strength (the force needed to tear the ligament). In fact, science has shown that the deeper you squat the safer it is on the ligaments of your knee.
Harmful shear forces are dramatically decreased due to an increase in compression. Also, the muscles in our legs work together to stabilize the knee. As we squat the hamstrings work with the quadriceps to counteract and limit excessive movement deep inside the knee.
Thus, provided good technique is used the ACL stays unharmed no matter how deep the squat!
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To read more on debunking the myth that deep squats are harmful to the knees, check out this article: https://squatuniversity.com/…/debunking-squat-myths-are-de…/
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Squat University is the ultimate guide to realizing the strength to which the body is capable of. The information within these pages are provided to empower you to become a master of your physical body. Through these teachings you will find what is required in order to rid yourself of pain, decrease risk for injury, and improve your strength and athletic performance.
同時也有1部Youtube影片,追蹤數超過483的網紅Boris Foong,也在其Youtube影片中提到,IMPULSE (Full Continuous Mix) Mixed by Boris Foong - Recorded on February 2017 DJ Commentary Can't stress enough to state that "Saving Light", by Gar...
shear stress 在 Greta 林昱綺 Facebook 的最佳解答
【不刻意跨步也可以跑出長步幅】
「企者不立,跨者不行」(老子第二十四章)
許多跑者常會犯一個嚴重的錯誤:過度跨步。這是當腳掌跨到臀部之前落地,就會形成剪應力(Shear Stress),而剪應力是造成膝關節受傷的主因。試想一根筷子垂直於桌面撐著,手掌用力從頂端往下施壓,由於沒有水平分力,所以不會形成剪應力,因此筷子不易折斷。但是當竹筷子斜撐在桌面,你的手掌仍由上向下逐漸加壓,它就會從中折斷。
同樣的道理也發生在跑步落地時,當你的腳掌落在臀部的正下方,就像一根筷子直立在桌面上,垂直向下的衝擊力與腿部的力學結構平行,因此不會有剪應力產生,但當你的腳跨出去的幅度加大,落地點跑到臀部(質心)前方,向前跨得愈遠,剪應力就愈大,傷害發生的機率也就愈高。剪應力所造成的運動傷害最常發生在膝蓋,由於膝蓋剛好位在大腿與小腿的接合處,當剪應力發生時就會造成不當滑動,滑動引起摩擦和拉扯,久而久之傷害就產生了。影片下方的示範動作就是腿部最容易受傷的跑法。
但不少人擔心「不跨步,步幅不就會變得很小嗎?」
只要我們知道步距長短的三項成因中並沒有跨步這一項,就可以了解這樣的擔心是多餘的,這三項成因分別是:
1.前傾角度:角度愈大,向前落地的距離愈遠。
2.腳掌拉起後離地的高度:腳掌離地愈高,落地的空間變大,自然能飛騰出較遠的距離。
3.慣性:雙腳皆離地後,失去支撐,此時沒有任何加速度,除了空氣阻力之外,身體前進保持慣性速度,此慣性速度是由支撐期前傾時的加速度所「加」出來的。
比如某位跑者前傾15度,加速到每公里3分半速,此時腳掌離地的高度自然就相當高,每步才有辦法飛躍出1.6公尺。想像一下:若這位跑者的腳掌最高只拉高到腳踝的話,有可能每步飛躍出1.59公尺嗎?(步速每公里3分30秒 = 285.71公尺/分鐘,假設此跑者的步頻是每分鐘180步→ 每步1.6公尺)。
老子說「企者不立,跨者不行」(老子第二十四章)。白話的意思是說踮起腳跟反而站不久,大跨步前進反而跑不遠。
「無為而無不為」,不刻意跨步,反而可以跑出較長的步幅,這其實就是順應自然的道理。今天心血來潮請叉傑克和依婷幫忙拍下來用影片跟大家分享……
shear stress 在 徐國峰 HSU KUO FENG Facebook 的最佳貼文
【不刻意跨步也可以跑出長步幅】
「企者不立,跨者不行」(老子第二十四章)
許多跑者常會犯一個嚴重的錯誤:過度跨步。這是當腳掌跨到臀部之前落地,就會形成剪應力(Shear Stress),而剪應力是造成膝關節受傷的主因。試想一根筷子垂直於桌面撐著,手掌用力從頂端往下施壓,由於沒有水平分力,所以不會形成剪應力,因此筷子不易折斷。但是當竹筷子斜撐在桌面,你的手掌仍由上向下逐漸加壓,它就會從中折斷。
同樣的道理也發生在跑步落地時,當你的腳掌落在臀部的正下方,就像一根筷子直立在桌面上,垂直向下的衝擊力與腿部的力學結構平行,因此不會有剪應力產生,但當你的腳跨出去的幅度加大,落地點跑到臀部(質心)前方,向前跨得愈遠,剪應力就愈大,傷害發生的機率也就愈高。剪應力所造成的運動傷害最常發生在膝蓋,由於膝蓋剛好位在大腿與小腿的接合處,當剪應力發生時就會造成不當滑動,滑動引起摩擦和拉扯,久而久之傷害就產生了。影片下方的示範動作就是腿部最容易受傷的跑法。
但不少人擔心「不跨步,步幅不就會變得很小嗎?」
只要我們知道步距長短的三項成因中並沒有跨步這一項,就可以了解這樣的擔心是多餘的,這三項成因分別是:
1.前傾角度:角度愈大,向前落地的距離愈遠。
2.腳掌拉起後離地的高度:腳掌離地愈高,落地的空間變大,自然能飛騰出較遠的距離。
3.慣性:雙腳皆離地後,失去支撐,此時沒有任何加速度,除了空氣阻力之外,身體前進保持慣性速度,此慣性速度是由支撐期前傾時的加速度所「加」出來的。
比如某位跑者前傾15度,加速到每公里3分半速,此時腳掌離地的高度自然就相當高,每步才有辦法飛躍出1.6公尺。想像一下:若這位跑者的腳掌最高只拉高到腳踝的話,有可能每步飛躍出1.59公尺嗎?(步速每公里3分30秒 = 285.71公尺/分鐘,假設此跑者的步頻是每分鐘180步→ 每步1.6公尺)。
老子說「企者不立,跨者不行」(老子第二十四章)。白話的意思是說踮起腳跟反而站不久,大跨步前進反而跑不遠。
「無為而無不為」,不刻意跨步,反而可以跑出較長的步幅,這其實就是順應自然的道理。今天心血來潮請叉傑克和依婷幫忙拍下來用影片跟大家分享……
shear stress 在 Boris Foong Youtube 的最佳解答
IMPULSE (Full Continuous Mix)
Mixed by Boris Foong - Recorded on February 2017
DJ Commentary
Can't stress enough to state that "Saving Light", by Gareth Emery & Standerwick with Haliene's vocals, inspired me to compile #IMPULSE. It is tracks like these that reaches out to my heart and soul through difficult times, each of those words in that song is so impactful that it manifested in me. "The Night is Ours" and "Destiny" are also tracks to look out for, it projects instrumentally what this compilation #IMPULSE meant to me.
When I was in the moment of self-reflection one night, it came to me that in order to love who I am, I cannot hate the experiences that shaped me. At that moment, I realised that I must embrace my impulsiveness, thus the name of this compilation mix; IMPULSE.
I want none of these tracks to be anything really familiar/bangers, but yet sustain my trance/progressive music flavour and mixing style as a DJ. Many of times, we got so caught up with the big hitters that we overlooked at what's currently present. To me, whatever I believe on the inside, is what manifest on the outside. The simplicity of things is actually enough to create the bigger picture. Abundance.
-Boris Foong
P/S: Our homeboy Gautam Khaw's latest ID sees fit in #IMPULSE, gotta give it to him for the clean solid mixdown, his taste and talent deserves some recognition.
#IMPULSE DJ Tracklist
1. Circulatory Disturbance (Ghoeyash Remix) - Robert R. Hardy
2. The Night Is Ours - Alpha 9
3. Tears Of The Sun - Alan Morris & Marco Cera
4. In And Out Of Love feat. Sharon Den Adel (Diversion Remix) - Armin van Buuren, Sharon Den Adel
5. Lonely Time - L.O.M.
6. Destiny - Andrew Bayer & Ilan Bluestone
7. Returning - Maor Levi
8. Daylily - Axis
9. Gravity - Marcus Santoro
10. Valor - Jason Ross
11. Zero Gravity - Dis Play & Max Meyer
12. Higher Love - Seven Lions & Jason Ross feat. Paul Meany
13. Balearic Balls - Above & Beyond
14. One More Time (Alexander Popov Remix) - Christian Burns, Alexander Popov
15. Alpha Shear - SCHALA
16. Take it All feat. Hansen Tomas - Jochen Miller, Andrew Rayel, Hansen Tomas
17. Asphalt - Protoculture
18. ID - Gautam Khaw
19. Rebirth - Mark Sixma Pres. M6 & Standerwick
20. Saving Light feat. HALIENE - Gareth Emery & Standerwick
Mixcloud: mixcloud.com/borisfoongdj/boris-foong-warm-up-set-2016-marlo-david-gravell-zouk-mainroom/
Facebook: facebook.com/borizbenji
Instagram: borisfoong
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