Adarq.org
Performance Area => Article & Video Discussion => Topic started by: LBSS on April 09, 2010, 12:29:40 pm
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All stolen from Laisle Macdoneldz.
Eur J Appl Physiol Occup Physiol. 1987;56(4):412-8. Links
Metabolic response of endurance athletes to training with added load.
* Rusko H,
* Bosco CC.
Endurance athletes were divided into experimental (n = 12) and control (n = 12) groups to investigate the effects of extra-load training on energy metabolism during exercise. A vest weighing 9%-10% body weight was worn every day from morning to evening for 4 weeks including every (n = 6) or every other (n = 6) training session. After 4 weeks the control group had a lower blood lactate concentration during submaximal running, whereas the experimental group had significantly higher blood lactate and oxygen uptake (p less than 0.01--p less than 0.05), and a lower 2 mmol lactate threshold (p less than 0.05) and an increased blood lactate concentration after a short running test to exhaustion (p less than 0.05). Those experimental subjects (n = 6) who used the added load during every training session had a lower 2 mmol lactate threshold, improved running time to exhaustion, improved vertical velocity when running up stairs and an increased VO2 during submaximal running after the added load increased anaerobic metabolism in the leg muscle during submaximal and maximal exercise. An increased recruitment and adaptation of the fast twitch muscle fibres is suggested as the principal explanation for the observed changes.
Med Sci Sports Exerc. 1986 Aug;18(4):415-9. Links
The effect of extra-load conditioning on muscle performance in athletes.
* Bosco C,
* Rusko H,
* Hirvonen J.
Fourteen sprinters were assigned to an experimental group (N = 7) and a control group (N = 7) in order to study the effects of 3 wk of extra-load conditioning. The extra-load conditioning was achieved by the athletes wearing special vests containing weights (7-8% body mass). The vests were used from morning to evening and during 3-5 training sessions/wk for 3 wk. No changes in the ordinary training regime were allowed, except the use of the vest by the experimental group. A jumping test battery and short running test on a treadmill were utilized to measure explosive power characteristics and the anaerobic performance of the subjects. While the control group showed no changes in any of the variables studied, the experimental subjects significantly improved their jumping heights in squat jumps with and without extra loads; their jumping heights in drop jumps and mechanical power output in 15 s of jumps. No changes in lactate levels or in running times to exhaustion were observed in response to the extra-load conditioning. The improvement of jumping performances could be due to a fast neurogenic adaptation to the new requirements.
: Acta Physiol Scand. 1985 Aug;124(4):507-13. Links
Adaptive response of human skeletal muscle to simulated hypergravity condition.
* Bosco C.
The mechanical behaviour of leg extensor muscles of five international-level athletes was evaluated during 13 months training period. Drop jumps, average mechanical power during 15 S continuous jump, and vertical jumps performed with and without extra weights were used to measure explosive power characteristics. The data recorded in vertical jumps was utilized for construction of force-velocity relationship (F-V curve). The athletes did not show improvement in any of the variables studied after 12 months of intensive systematic training programme. It was assumed that the subjects already had reached their upper limit of performance. However, after that the athletes underwent a simulated 3 weeks high-gravity period. The hypergravitational condition was created by wearing a special vest filled with extra loads (11% of BW). The vest was used from morning to evening. No changes in the ordinary training programme were allowed. After the simulated high-gravity conditioning period significant improvement in almost all the variables studied was observed (P less than 0.05-0.001). Vertical jump performance was enhanced from 44.3 to 54.9 cm. The F-V curve remained stable all year but after hypergravity period shifted markedly to the right. The drastic improvement was attributed to be caused by a fast adaptation to the new functional requirements (I.I g). Therefore, once the biological adaptation occurred the mechanical behaviour of the athlete's leg extensor muscle was similar to that which could be experienced in a field at low gravity condition (0.9 g). Adaptive response to the hypergravity conditioning was speculated to occur mainly at neurogenic level and less in myogenic component.
Eur J Appl Physiol Occup Physiol. 1984;53(2):149-54. Links
The influence of extra load on the mechanical behavior of skeletal muscle.
* Bosco C,
* Zanon S,
* Rusko H,
* Dal Monte A,
* Bellotti P,
* Latteri F,
* Candeloro N,
* Locatelli E,
* Azzaro E,
* Pozzo R, et al.
Eleven international jumpers and throwers engaged in year round training were divided into experimental (n = 6) and control (n = 5) groups. The experimental group was tested before and after a 3 weeks simulated hypergravity period, and again 4 weeks after the hypergravity period. The high gravity condition was created by wearing a vest weighing about 13% of the subjects body weight. The vest was worn from morning to evening including the training sessions, and only removed during sleep. The daily training of all subjects consisted of classical weight training and jumping drills. No changes in the ordinary training program were allowed in the experimental group, except for the use of the vest. Vertical jumps, drop jumps and a 15 s continuous jumping test were used to measure the explosive power characteristics of the subjects. After the hypergravity period the experimental subjects demonstrated significant (5-10%, P less than 0.05-0.01) improvements in most of the variables studied: however, 4 weeks after cessation of the high gravity period they tended to return towards the starting values. No changes were observed in the results of the control group. The improvement observed in the experimental subjects was explained as fast adaptation to the simulated high gravity field. It is suggested that adaptation had occurred both in neuromuscular functions and in metabolic processes.
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nice studies man.. the increase in vert of all of those is pretty impressive, especially the 44-54cm one.
I knew a kid who did this, khalil, he's in my videos on youtube.. He had stopped wearing the vest after our first few dunk sessions, instead he started lifting. After he started lifting his vert did sky rocket, but I have no idea how much wearing that vest all of the time effected him. One thing he has though, is major knee tendonitis problems. He would wear the vest all day + play games in the vest, I wouldn't be surprised if the overzealousness of that vest caused alot of his knee tendonitis issues.
interesting stuff though..
peace
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It is suggested that adaptation had occurred both in neuromuscular functions and in metabolic processes.
What kind of metabolic processes?
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It is suggested that adaptation had occurred both in neuromuscular functions and in metabolic processes.
What kind of metabolic processes?
I would imagine, enzymes/mitochondria related to anaerobic power production, stuff like that.
http://en.wikipedia.org/wiki/Mitochondrion
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I've always associated mitochondria with aerobic prowess... but it seems they actually generate ATP. Interesting.
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The Longitudinal Effects of Resisted Sprint Training Using Weighted Sleds vs. Weighted Vests
Clark, Kenneth P1; Stearne, David J1; Walts, Cory T2; Miller, Anthony D1.
Abstract.
Clark, KP, Stearne, DJ, Walts, CT, and Miller, AD. The longitudinal effects of resisted sprint training using weighted sleds vs. weighted vests. J Strength Cond Res 24(12): 3287-3295, 2010-The purpose of this study was to determine the longitudinal effects of weighted sled (WS) and weighted vest (WV) sprint training on maximum velocity sprint performance and kinematics. Twenty male collegiate lacrosse players were randomly assigned to a WS group (n = 7) towing 10% body mass, a WV group (n = 6) loaded with 18.5% body mass, or an unresisted (UR) active control group (n = 7). All subjects completed 13 training sessions over 7 weeks. Pre- and post-test measures of sprint time and average velocity across the distance interval of 18.3 to 54.9 m were used to assess sprint performance, whereas high-speed video (300 Hz) and motion-analysis software were used to analyze stride length, stride rate, ground contact time, and flight time. A 3 × 2 repeated measures analysis of variance was performed for each dependent variable and revealed no significant between-group differences for any of the sprint performance or kinematic stride cycle measures. Effect size statistics suggested small improvements in 18.3- to 54.9-m sprint time and average velocity for the UR group but only trivial improvements for the WS and WV groups. With regard to sprint performance, the results indicate that WS and WV training had no beneficial effect compared with UR training. In fact, for the loads used by WS and WV in this study, UR training may actually be superior for improving sprint performance in the 18.3- to 54.9-m interval.
© 2010 National Strength and Conditioning Association.
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That almost every weighted vest study to show positive benefit uses a light (~<10% bw) vest worn all the time makes me think the adaptation is primarily neuromuscular.
Ditto, on the danger of increasing tendinitis risk with the increased load. A good reason to make sure you get really lean before trying anything like this.
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I use a weight vest all the time with the guys I train but I am careful with the exercises I use it for. Anything with high landing forces is out (running jumps of any variety, depth jumps, jumps requiring low gct such as tuck jumps, hurdle jumps etc) but I love them for things like seated jumps (jumping from a seated position), box jumps, frog jumps, paused jumps, and all bodyweight upper body exercises. I also like to throw them into the mix for a few different things like squatting and deadlifting on occasion, but this is done very rarely and more for variety.
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Do you guys believe it prevents natural movement in the purest sense.
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Do you guys believe it prevents natural movement in the purest sense.
anything short of nudity prevents natural movement. we've been fucked on that score since we left eden.
Genesis 3:6-13 (KJV)
And when the woman saw that the tree was good for food, and that it was pleasant to the eyes, and a tree to be desired to make one wise, she took of the fruit thereof, and did eat, and gave also unto her husband with her; and he did eat.
And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together, and made themselves aprons.
And they heard the voice of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God amongst the trees of the garden.
And the LORD God called unto Adam, and said unto him, Where art thou?
And he said, I heard thy voice in the garden, and I was afraid, because I was naked; and I hid myself.
And he said, Who told thee that thou wast naked? Hast thou eaten of the tree, whereof I commanded thee that thou shouldest not eat?
And the man said, The woman whom thou gavest to be with me, she gave me of the tree, and I did eat.
And the LORD God said unto the woman, What is this that thou hast done?
And the woman said, The serpent beguiled me, and I did eat.
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i attribute my weighted vest to my groin strain... to be able to jump/sprint with weighted vests, you need a really good, snug fitting vest.. mine moves around too much, i think hill sprints while holding onto it with one arm is what caused this 1+ week of groin pain so far.. makes sense too when you think about it.
so ya be careful with it hah.. i liked it though for long duration walking.
i have sprinted/jumped in vests before, but they were really good ones.. fit so snug.. makes a big difference, really important.