x*******6
发帖数: 994 | 1 A test of America's homeland missile defense system found a problem. Why did
the Pentagon call it a success?
By DAVID WILLMAN
REPORTING FROM WASHINGTON | JULY 6, 2016, 3 A.M.
If North Korea ever unleashed nuclear-armed missiles against America, the
defense of U.S. cities and towns would depend to no small degree on
something called a divert thruster.
These small rocket motors would be counted on to keep U.S. anti-missile
interceptors on target as they hurtled through space toward the incoming
wa... 阅读全帖 |
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c**i
发帖数: 6973 | 2 (1) Igor Sikorsky (1889-1972; born in Kiev, Russian Empire (present day
Ukraine)) immigrated to US in 1919, founded Sikorsky Aircraft Corporation
in 1923 and sold it to United Technologies Corp in 1929.
Sikorsky
http://en.wikipedia.org/wiki/Sikorsky
("Sikorsky is an English-language respelling of the Slavic surname Sikorski.
Derived from the Polish word sikora – meaning 'chickadee/tit' – it was
originally the name of a noble Polish-Lithuanian Commonwealth family")
(2) Those who follows me know ... 阅读全帖 |
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p*********l
发帖数: 26270 | 3 youtube上面有很多routine。我觉得HIIT有几个要点吧：
1 - 强度要够大，所以时间不能太长，10-15分钟差不多要能练的很累，能大喘气高心
跳，不然可以考虑加重量
2 - 组间有短暂休息，第一次练不熟悉的routine，可以休息30秒左右，如果练完感觉
不够累，下次缩短到20秒，如果累得完成不了，可以适当延长组间休息
3 - 一般说来，要么是同样的个数尽可能做得快，要么是同样的时间尽可能做得多，总
之要尽量在短时间内达到高强度的目的
举个例子：
9 sets of squat thrusters + burpees
每个set之间休息30秒左右
每个set 有10个动作，分别是
9 squat thrusters + 1 burpee
8 squat thrusters + 2 burpees
.....
1 squat thrusters + 9 burpees
squat thruster我说的是这种，你需要找到自己合适的重量，因为是高rep训练，不能
太重 |
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t****a
发帖数: 52 | 6 呵呵，谢谢。
今天中午fasting状态tabata了4组，出汗不少，排水上称给自己点动力
下午的wod似乎又能减不少水膘
Push Press
5-5-5-5-5 Use heaviest weight possible
“Death By”
With a continuously running clock perform:
1 Thruster, 95/65 lbs and 1 Double Under in the first 1 min
2 Thrusters, 95/65 lbs and 2 Double Unders in the second 1 min
3 Thrusters, 95/65 lbs and 3 Double Unders in the third 1 min …
Continuing this forever until until reps cannot be met on according minute. |
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T**********e
发帖数: 29576 | 7 给国际空间站补给飞船。一级火箭装了回收支架，在大西洋控制降落成功。
SpaceX Claims Milestone With Bold Reusable Rocket Test
SpaceX's audacious plan to return a rocket to Earth after a space launch
today (April 18) may not have gone perfectly, but the company's founder
still considers it a success — one that could help lay the foundation for
fully reusable rockets in the future.
SpaceX tried to guide the first stage of its Falcon 9 rocket back to Earth
in an ocean splashdown today during the launch of the company's unmanned
Drago... 阅读全帖 |
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T**********e
发帖数: 29576 | 8 本月发射的F9火箭一级计划海上平台回收。
SpaceX’s next launch is set for Dec. 16 from Cape Canaveral with an
unmanned Dragon cargo ship carrying more than 3,700 pounds of supplies and
experiments for the International Space Station.
After releasing the rocket’s upper stage to propel the Dragon supply ship
into orbit, the lower part of the booster will fire a subset of its nine
engines for a re-entry burn to guide it toward a designated landing zone in
the Atlantic Ocean northeast of Cape Canaveral.
The rocket will ... 阅读全帖 |
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G*******n
发帖数: 6889 | 9 http://gbtimes.com/china/china-racing-make-2020-launch-window-m
Andrew Jones
2016/02/22
Mars Exploration Rover Spirit captures a stunning view as the sun sank below
the rim of the Gusev crater on Mars on May 19, 2005.Mars Exploration Rover
Spirit captures a stunning view as the sun sank below the rim of the Gusev
crater on Mars on May 19, 2005. (Photo: NASA/JPL/Texas A&M/Cornell)
Tags:
China's space programMarsNational Space Science CenterChina Aerospace
Science and Technology CorporationEur... 阅读全帖 |
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j****3
发帖数: 2836 | 10 http://www.chinadefenseobservation.com/?p=4243
China claims to have a working version of NASA’s impossible engine orbiting
the Earth
Scientists in China claim they’ve created a working prototype of the ‘
impossible’ reactionless engine – and they say they’re already testing it
in orbit aboard the Tiangong-2 space laboratory. And will use it in
satellites ‘imminently’.
The radical, fuel-free EmDrive recently stirred up controversy after a paper
published by a team of NASA researchers appeared to ... 阅读全帖 |
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T**********e
发帖数: 29576 | 11 原来不仅是时钟上错，还中途受手机站干扰失去联系，service module分离混乱，照这
老爷公司的干活速度，怎么也得1年时间debug再无人试飞，3年内别想载人。到时候马
一龙要登火星了。
Timing is everything, especially in spaceflight, and that’s where Boeing’s
Starliner first had trouble. Thanks to a software glitch, Starliner
incorrectly set its internal clock hours before it launched, which meant
that after it separated from the rocket and reached space, the capsule
missed the moment it needed to fire some thrusters and push itself into the
right orbit. In a cruel twist, mission c... 阅读全帖 |
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x*******u
发帖数: 1180 | 13 10/24/12
Thrusters
3-3-3-3. 45lb-50-55-60
5 min AMRAP
Thruster (45lb)
20
5 min AMRAP
5 burpees, 10 wall ball (10)
4 |
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x*******u
发帖数: 1180 | 14 10/24/12
Thrusters
3-3-3-3. 45lb-50-55-60
5 min AMRAP
Thruster (45lb)
20
5 min AMRAP
5 burpees, 10 wall ball (10)
4 |
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x*******u
发帖数: 1180 | 15 我一个假期长了三磅， 还好！ 现在饮食上毫无节制， 爱谁谁。
你真的停了crossfit?! 我们今天的项目如下：
kettle bell swing for 8 min
Then
Thruster
3-3-3-3
Then
3-6-9-12-9-6-3
Thruster
Burpee
Then
1 min prank, 30 sec side prank for each side, 1 min prank.
要不要重新加入组织再受虐？ |
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x*******u
发帖数: 1180 | 16 我一个假期长了三磅， 还好！ 现在饮食上毫无节制， 爱谁谁。
你真的停了crossfit?! 我们今天的项目如下：
kettle bell swing for 8 min
Then
Thruster
3-3-3-3
Then
3-6-9-12-9-6-3
Thruster
Burpee
Then
1 min prank, 30 sec side prank for each side, 1 min prank.
要不要重新加入组织再受虐？ |
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x*******u
发帖数: 1180 | 17 02/08/13
Thruster
3-3-3-3
55lb-60lb-65lb-70lb
7min AMRAP
3 thruster
3 chest to bar pull up
6,6-9,9- 12,12-15,15-18,18 etc.
68 |
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x*******u
发帖数: 1180 | 18 02/08/13
Thruster
3-3-3-3
55lb-60lb-65lb-70lb
7min AMRAP
3 thruster
3 chest to bar pull up
6,6-9,9- 12,12-15,15-18,18 etc.
68 |
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x*******u
发帖数: 1180 | 19 03/15/13
Squat clean thruster
5-3-1-1-1-1
75lb
Then
Squat clean thruster time ladder
45lb, 10 |
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s****e
发帖数: 1984 | 20 赞啊，昨天10 mile，今天不用歇着.100 thrusters...不知道thruster是什么。去
youtube查了，我也ORZ. |
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s*******n
发帖数: 2029 | 21 埃里克森给出了每天练习的原则：“训练需要有强度，但不需要太长时间；确保假期结
束后，准备好继续提升，而不是重新调整恢复。” 这份训练计划分为三个部分
一、每天练习的内容：
1、100—200次仰卧起坐，100次下蹲和80—100次俯卧撑。
2、引体向上和Toes to bar (动作同引体向上，收腹双脚向上)，是对上肢力量
最好的练习。尽力每周完成150次，如果每天做30次，对于保持肌肉张力是非常好的。
3、Thrusters(下蹲后向上推举杠铃)也是一项非常好的力量训练，尽量每周完成
100次(30公斤)，每天20次。
二、根据健身器材情况，在指定日完成其中一项：
周一(12月2日、9日、16日、23日、30日)
选择下列项目之一：
A、20分钟单车，其中20秒保持高强度，难度级别15，转速大于80，40秒放松。
B、慢跑30分钟，速度为每公里5分钟。
C、5次Burpees(贴地俯卧撑+跳)、10次俯卧撑、15次下蹲、15次仰卧起坐为1组，
完成15组。
周三(12月4日、11日、18日、25日、1月1日)
选择下列项目之一
A、上坡跑，70%最快速度，10乘100米。
B、上坡跑... 阅读全帖 |
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p********f
发帖数: 5148 | 22 很魔鬼。
Angie --- 100 pull-ups, push-ups, sit-ups, squats for time
Cindy --- AMRAP in 20 minutes: 5 pull-ups, 10 push-ups, 15 squats
Diane --- 21-15-9 reps for time: deadlifts 225#/155#, handstand push-ups
Elizabeth --- 21-15-9 reps for time: squat cleans (135#/95#), ring dips
Fran --- 3 rounds, 21-15-9 for time: thrusters (95/65), pull-ups
Grace --- 30 Clean & Jerk for time (135#/95#/65#)
Helen --- 400 meter run, 21 kettlebell swings, 12 pullups
Jackie --- 1000 meter row, 50 thrusters 45# , 30 pul... 阅读全帖 |
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O*******d
发帖数: 20343 | 23 这种低级错误竟然发生在NASA， 不可想象啊。
The metric/imperial mix-up
The loss of the craft was the result of several factors, including a design
flaw that resulted in asymmetric torque, software errors in the small
forces model, and management inattention. The metric/imperial
mix-up that destroyed the craft was caused by a human error in the
software development, back on Earth[1]. The thrusters on the
spacecraft, which were intended to control its rate of rotation, were
controlled by a computer that underestimate |
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a***c
发帖数: 2443 | 24 the second picture is a hall thruster if I'm not mistaken. |
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x****u
发帖数: 12955 | 25
in
If you are ignorant of the subject, be a little bit more humble doesn't hurt
.
Two object on similar orbit will have very similar speed. That's determined
by physics. So there's absolutely no difficulty in keeping the relative
speed very low. The return module only need to gradually raise its orbit to
match the command module, all while keep a very safe distance away. Then
once the orbit matches, fire a thruster for a few seconds to gain speed on
the command module and wait for the grad... 阅读全帖 |
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T**********e
发帖数: 29576 | 28 SpaceX的实用F9火箭一千米回收实验
SpaceX plans to recover stages when customers allow
BY STEPHEN CLARK
Encouraged by the soft landing of a Falcon 9 rocket's first stage in the
Atlantic Ocean after liftoff April 18, SpaceX plans a series of stage
retrieval tests over the next few months, but only on missions where the
launcher has enough leftover fuel to accomplish the complicated re-entry
maneuvers required to safely return a rocket to Earth.
SpaceX hopes the experiments will lead to returning a rocket i... 阅读全帖 |
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y***k
发帖数: 9459 | 29 我弟早就基本放弃化学能的研发进化了。现在我弟早就开始新概念推进装置的研究了，
现在NASA在搞的两个项目，一个是等离子推进 ion thruster，已经基本成型，下一步
是用可控核裂变甚至核聚变提供更高效的能源。另一个是更超前的hyper drive，又有
琵琶半遮面的说已经closer to reality了。现在窝工应该调转方向，加大力气研制新
概念推进装置。可喜的是，窝工航天体系内还是有有识之士的，在《2035年航天研究长
远规划》里提到了新概念推进的预研。但这远远是不够的，我老再次高瞻远瞩的指出，
全力投入到等离子推进装置，并预先研制hyper drive，这才能屹立于世界民族之林 |
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m**c
发帖数: 7349 | 30 The rocket climbed in a clear nighttime sky, and a camera fixed to the
vehicle showed the Long March 2F’s four strap-on YF-20B booster engines
dropping away about two-and-a-half minutes into the flight. Moments later,
the core stage jettisoned and the second stage’s main engine and vernier
steering thrusters ignited as planned. |
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m**c
发帖数: 7349 | 31 A vernier thruster is a rocket engine used on a spacecraft for fine
adjustments to the attitude or velocity of a spacecraft. |
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p*********3
发帖数: 8525 | 32 美国时间 11 月 17 日，众人翘首以盼的 NASA 关于 EmDrive 的论文终于发表出来了
，论文结果显示 EmDrive 在没有燃料的情况下确实能产生推进力：每千瓦 1.2 毫牛。
资讯业界
NASA关于EmDrive最新论文发布！人类或将进入全新能源时代
NASAnasa中文官网emdrive引擎emdrive 曲速引擎
作者：亚萌
2016/11/20 14:14
美国时间 11 月 17 日，众人翘首以盼的 NASA 关于 EmDrive 的论文终于发表出来了
，论文结果显示 EmDrive 在没有燃料的情况下确实能产生推进力：每千瓦 1.2 毫牛。
本篇论文题目为"Measurement of Impulsive Thrust from a Closed Radio-Frequency
Cavity in Vacuum"，这跟 2 个多月前José Rodal 博士在 Nasa Spaceflight
论坛爆料的题目一模一样，一个字不差！（所以各位如果要搜集关于NASA 的各种小道
消息，Nasa Spaceflight 上的料还是值得一听的。）
论文刊登于美国航空航... 阅读全帖 |
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C***J
发帖数: 7594 | 33 Now we know how Elon Musk plans to get 1 million people to Mars.
At a conference in Mexico today (Sept. 27), the SpaceX founder and CEO
unveiled the company's Interplanetary Transport System (ITS), which will
combine the most powerful rocket ever built with a spaceship designed to
carry at least 100 people to the Red Planet per flight.
If all goes according to plan, the reusable ITS will help humanity establish
a permanent, self-sustaining colony on the Red Planet within the next 50 to
100 years... 阅读全帖 |
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m********5
发帖数: 17667 | 34 From there we do not need to use chemical engine to launch them. Ion
thruster would be enough. The only problem will be can we create a foundry
working without water? If someone can do this, he/she will start the space
era. |
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m**c
发帖数: 7349 | 35 At a height of about 100 km, the Falcon 9 fairing separates from the second
state rocket, traveling at Mach 10.
Each of the two 1000-kg half-shells tumbles down at high speeds; cold
nitrogen thrusters will be used to stabilize the awkward-shaped fairing
piece and orient it into a more aerodynamic posture.
After it has fallen to an altitude of about 8 km and has slowed down
considerably by atmospheric drag, a GPS-equipped steerable parachute (
parasail) will be deployed which will “gently” guide ... 阅读全帖 |
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x*******6
发帖数: 994 | 36 Investigation into Zuma failure reportedly lays blame on Northrop Grumman
April 9, 2018 Stephen Clark SpaceX’s Falcon 9 rocket lifted off Jan. 7 from
Cape Canaveral with the Zuma mission. Credit: SpaceX Government
investigators have exonerated SpaceX’s Falcon 9 rocket in the loss of a top
secret space mission known as Zuma in January, blaming a malfunction in a
component modified by Northrop Grumman that connected the launcher with its
classified payload, according to the Wall Street Journal. Ci... 阅读全帖 |
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l*****O
发帖数: 402 | 37 我来教教你吧，深蹲主要练腿，只练到一点屁股。但深蹲是练臀前最好的warm up，你
要热起来，练臀才有效果。练臀最佳是各种臀桥（比如臀桥thruster等），加重量，或
用弹力带（美丽巴蕾了解一下）。然后是用弹力带的monster walk, x band walk，再
然后是硬拉（包括罗马尼亚硬拉），还有带重量的swing（主要用plate或kettle bell
）. 就算fast feet效果都比深蹲好。 |
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o*****a
发帖数: 2335 | 38 2.激光推进原理及特点
2.1 激光推进原理
激光推进的基本原理是将远距离激光能量导入推进器(thruster)中的推进剂中,使其温
度急剧升高,形成高温高压气体或等离子体,然后从喷管(nozzle)中喷射出来,从而产生
推力。
激光推进系统主要包括激光系统、光束发射与控制系统、光船三部分。从是否消耗自身
携带工质看，激光推进的驱动模式可分为大气呼吸模式和火箭烧蚀模式。大气呼吸模式
是将经进气道吸入的空气作为工质，激光击穿空气，产生激光支持的等离子体爆轰波，
推动光船前进的推进模式。这种模式不用消耗自身携带的推进剂（图2）。火箭烧蚀模
式是指激光加热光船自身携带的工质（气体、液体和固体）产生高温高压等离子体，经
喷管推动光船前进的推进模式（图3）。两种激光推进模式都是通过激光与工质的相互
作用，将激光能量转化为等离子体热能，最终转化为光船的动能。当飞行器位于大气层
内时，可利用飞行器尾部抛物面反射镜聚焦地基激光器发出的激光能量，在焦点处点燃
空气等离子体进行推进（大气
模式），这时飞行器不消耗自身质量。当处于大气上层（30km以上）或外空间时转为采
用自携工质（火箭烧蚀模式）。
烧蚀模... 阅读全帖 |
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a***s
发帖数: 1084 | 39 http://www.nbcnews.com/science/space/mysterious-x-37b-space-pla
No one seems to know much about the Air Force's X-37B secret space plane
except that it appears to be working exactly as designed. The unmanned
Boeing-built craft, which resembles a miniature space shuttle, returned to
Earth on Friday after nearly two years — 674 days, to be exact — in space.
It's the X-37B program's third mission to space and by far the longest.
The plane landed at 9:24 a.m. local time on Oct. 17 at Vandenberg Air ... 阅读全帖 |
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c********n
发帖数: 2244 | 40 本周的飞船游戏，贴在田野会所了，今天晚上10点要交。
http://www.mitbbs.com/clubarticle_t/Countryclub/2279853.html
以下是作业要求。
1 pt - The program draws the ship as an image.
1 pt - The ship flies in a straight line when not under thrust.
1 pt - The ship rotates at a constant angular velocity in a counter
clockwise direction when the left arrow key is held down.
1 pt - The ship rotates at a constant angular velocity in the clockwise
direction when the right arrow key is held down.
1 pt - The ship's orientation is independent ... 阅读全帖 |
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T*********I
发帖数: 10729 | 41 KungfuDogg
量子真空虚拟等离子体推进器，俗称Q-thruster听上去很像是科幻故事中出现的产物。
事实上它已经被做出来了，如下图这枚EmDrive引擎被两组 独立的不同研制团队开发测
试，目前已经通过美国航天署NASA的认证。这枚引擎最大的特点就是不需要借助化学燃
料。听上去似乎违反了已知的推进加速器设计基础甚至牛顿运动定律-火箭推进器必须
要燃烧化学燃料才能推进。
这枚引擎的推进加速原理是什么呢？据外媒报道，该推进器利用的是微波，从太阳能或
其他形式能量中的电子产生的微波，[据维基百科]EmDrive 的实质其实只是一个微波共
振空腔（microwave resonating cavity），而形状则是一个密封的缺顶圆锥体。你启
动这个电动的微波产生器，随即它就开始在椎体内发射微波，微波在这个密闭空间内被
反复地反弹。
最初离子推进器最早于2009年由中国科学家团队完成并测试，这项技术的基本操作原理
最早是由一个名叫 Roger Shawyer 的英国人在好几十年前提出。最近由美国科学家
Guido Fetta独立于中国团队另行开发了这款称为EmDrive的引擎。由于它利... 阅读全帖 |
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w*******e
发帖数: 734 | 43 Obviously the author in this link confuses Q-Thruster with EMDrive |
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l****s
发帖数: 126 | 44 The NanoHELP group http://fzhang.utsi.edu/ at University of Tennessee is inviting well qualified Ph.D. students and exceptional postdoc researchers to join us for developing high-efficiency, low-cost and sustainable power and propulsion devices with the help of micro/nano technology. Our research ranges from fundamental understanding to system optimization with a strong interdisciplinary program. Projects include nanomaterials, micro fluidics, combustion, heat transfer, hydrogen fuel cells, el... 阅读全帖 |
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p********f
发帖数: 5148 | 45 I. “12 Days Of Christmas”
1 Power Snatch (95/65)
2 Ring Dips
3 Burpees
4 Pull-Ups
5 Toes to Bar
6 Push-Ups
7 Air Squats
8 Jumping Lunges
9 Box Jumps (20)
10 Wall Ball Shots (20/14)
11 Kettlebell Swings (53/35)
12 Thrusters (95/65)
This work out is performed just like
he song. The first round is one
Snatch, the second round is two Ring
Dips and one Snatch…etc. |
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x*******u
发帖数: 1180 | 46 三个月前开始crossfit，才接触力量训练。 deadlift我最好的记录125 lb, push
press 70lb, thruster 60lb, kettle bell 25lb.
举重的好些技术细节， 我还没掌握，昨儿三个师傅轮着给我讲， 越j讲我做的越不好
， 后来老大过来说， 薏米你不要想太多， just do it. 我这些个数字你们要笑话的
， 但谢谢飞姐的分享和大家的讨论， 学到很多。 |
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x*******u
发帖数: 1180 | 47 10/09/12
5 rounds 800m run
Rest 3 min after each round
Finish:37:30
Then
50 jackknife sit-up
看白板， 昨儿是3，3， 3，3 thruster, 然后是＂Fran", 好在没去， 要么死定了。
今天跑步尝试小步高频，觉得有点象老太太碎步走，省力是省力， 但不快。后面的一
圈， 不管了， 撒开丫子跑。原来举铁很厉害的白人队友， 有一半跑得是死去活来。
女子第一是个子比我苗条瘦小的阿邹， 看她的跨度很大， 过后会不会很累？ |
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x*******u
发帖数: 1180 | 48 录像里的红衣女子的柔韧性极好。看她做引体，整个身体象根弹力很好的橡皮筋。你现
在引体可以做几个？
我们有一次上课什么都不做， 就是100 个thruster, 够变态的吧。 我扛training bar
, 两边各加10lb, 35lb in total. 10个一组一组的熬完， 之后的两三天， 基本是爬
着过日子。 |
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f*******n
发帖数: 5241 | 49 我最多只做到11个，不会kipping。自从练5/3/1.体重一直在增加，
估计只能做5，6个了。
离做Fran还差太多，让我做完thruster就更做不动了。
练完以后全身酸疼的感觉是不是很好？：）
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c******t
发帖数: 1733 | 50 thruster这种动作，找到呼吸节奏很重要，你试试再合适的地方多一次呼气看看
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