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Performance Area => Strength, Power, Reactivity, & Speed Discussion => Topic started by: p.Esk. on August 31, 2011, 08:37:21 pm
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I hear that squatting 2x your bodyweight is GREAT, but when they say that do that mean like 1 rep max, 5 rep max. What about how long it takes us do godown and up. WHat are some good goals because i am only about 10 pounds away from having my one rep max be double my bodyweight.
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^ they are referring to your 1rm. KellyB said in one of his articles that a 1rm lift shouldn't take more than 4 seconds to complete, if i recall correctly.
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oh...i cant grind out that. I know that i will get it or not very quickly.
How much difference would it be if i could do it for five reps
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2 x bodyweight seems to be a good rule of thumb for many people. It's around the number where improving the jump gets harder because squat increases don't transfer as readily. And it's an easy enough goal that most male people can get there sort of quickly when their programming and motivation is okay.
That being said, more strength is always better in very general terms. But there is a point where more squat strength will not immediately and might actually never transfer to better jump height. This point varies from person to person, but I would assume it is higher than 2 x bodyweight for most. So going for 2 x for a set of 5 seems pretty reasonable.
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what about for sprinting>
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what about for sprinting>
I don't know about numbers here. But generally the same rules apply to any athletic task. Making max strength increases transfer to explosive events gets harder with continuing advancement. In your training you will therefore experience a shift in priorities for exercises. At the start the squat will make everything better but eventually you will have to incorporate more task specific training. What this consists of depends on your advancement as well training phase etc. Don't ask me about exercise selection for sprinters, I am not a very good runner and also don't have experience with it, so I can't give advice.
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
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^ I don't know much about sprinting, but the only thing I can think of is a change in mechanics leading to a less efficient (aka slower) way to sprint.
I'll creep back into the dark now and learn from afar...
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
what would you advise a sprinter to do then. In my opinion since trac doesn't start until late January, i need to get my acceleration faster because i have good top speed but am bad at the acceleration. I am naturally lighter and faster then strong, so basic strength work would help me.
But what would you put as main exercises for strength training and for reactive training.
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
Maximum velocity is by far the hardest quality to train. It's equal part tendon stiffness and leg strength. For well trained athletes max V can be improved with overspeed work (pulling, slight downhill runs, etc), lot's of max V work (flying 20s, etc), single leg bounding work, or changes to mechanics.
It's lower speed despite improved relative strength as measured by the squat. You see this because the squat becomes a poor measure of strength at maximum velocity. Even high school sprinters have their fastest 10-meter splits well under a second. At this speed an athlete must exhibit extremely brief powerful single leg ground contact and the squat does not accurately predict their ability to produce power in this movement. So basically, if you weigh 150 pounds and squat 300 pounds and run an 11 flat 100m (assume fastest 10m split of 0.9) and you increase your back squat to 400 pounds and your bodyweight to 200 pounds it's very likely that your 10m split will now be slower.
Note that this is less true for poorly trained athletes. If an athlete is running 13.0 seconds in the 100m then their max V may likely simply because they fatigue before they can accelerate to max V. If this is the case then overdistance work for endurance and increase in relative strength as measured by squat will increase their acceleration, maximum velocity and speed endurance.
Notice that this is less true for an untrained athlete.
-
what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
what would you advise a sprinter to do then. In my opinion since trac doesn't start until late January, i need to get my acceleration faster because i have good top speed but am bad at the acceleration. I am naturally lighter and faster then strong, so basic strength work would help me.
But what would you put as main exercises for strength training and for reactive training.
Depends. How do you know you have a good top speed and poor acceleration? What is your flying 30m speed? What is your 20m, 40m, 60m and 100m speed? What is your bodyweight and current squat max? Are you running indoor in janruary? Understand that it never hurts to squat more! Additionally, you never want to gain bodyweight! It's just that those who train for vertical jump can often make improvements if the gain a little weight if it comes with a large strength increase. But, no matter what you train for your goals should always be: increase your squat, decrease (or maintain) your bw. If your strength is really underdeveloped then be less strict about the bw goal.
Assuming you are not highly trained I would put the best exercise for strength training as the squat (all variations) and then the deadlift (a very distant second). For axillary lifts I would do weighted glute bridges or GHR or reverse hyper. For explosive lifts I would recommend the hang snatch. For reactive training you can do bounding, hurdle hops to sprints, standing triple jumps, etc. Additionally its a good idea to supplement your acceleration work with weighted pulling. Sled work will help your acceleration by allowing you to more easily transfer those gains your make in the weight room to the track.
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idk the times but at track last year, my starts were not so great, but i would end up catching up with everyone else. So i think for now i should only worry about getting my acceleration up. I max 275x1 full depth at 145 but i have a little bit of fat which i am takind care of.
Why cant i gain bw. I want to also get a good upper body physique for the ladies ;D ;D
I am going to work my way to squatting 295x5 from 200x5 i do now. That way i will have strong legs.
I clean instead of deadlift and i just cleaned 135x3 today and snatched 95x1 also.
WHat do you think about calf raises
NO ghr/reverse hyper...what about a back extension machine
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
Maximum velocity is by far the hardest quality to train. It's equal part tendon stiffness and leg strength. For well trained athletes max V can be improved with overspeed work (pulling, slight downhill runs, etc), lot's of max V work (flying 20s, etc), single leg bounding work, or changes to mechanics.
It's lower speed despite improved relative strength as measured by the squat. You see this because the squat becomes a poor measure of strength at maximum velocity. Even high school sprinters have their fastest 10-meter splits well under a second. At this speed an athlete must exhibit extremely brief powerful single leg ground contact and the squat does not accurately predict their ability to produce power in this movement. So basically, if you weigh 150 pounds and squat 300 pounds and run an 11 flat 100m (assume fastest 10m split of 0.9) and you increase your back squat to 400 pounds and your bodyweight to 200 pounds it's very likely that your 10m split will now be slower.
Note that this is less true for poorly trained athletes. If an athlete is running 13.0 seconds in the 100m then their max V may likely simply because they fatigue before they can accelerate to max V. If this is the case then overdistance work for endurance and increase in relative strength as measured by squat will increase their acceleration, maximum velocity and speed endurance.
Notice that this is less true for an untrained athlete.
Thanks for taking the time to answer this. Still, I don't understand your explanation. If an athlete increases his squat / bw ratio through an increase in bw and much larger increase in the squat, which mechanism makes that he is now slower?
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
Maximum velocity is by far the hardest quality to train. It's equal part tendon stiffness and leg strength. For well trained athletes max V can be improved with overspeed work (pulling, slight downhill runs, etc), lot's of max V work (flying 20s, etc), single leg bounding work, or changes to mechanics.
It's lower speed despite improved relative strength as measured by the squat. You see this because the squat becomes a poor measure of strength at maximum velocity. Even high school sprinters have their fastest 10-meter splits well under a second. At this speed an athlete must exhibit extremely brief powerful single leg ground contact and the squat does not accurately predict their ability to produce power in this movement. So basically, if you weigh 150 pounds and squat 300 pounds and run an 11 flat 100m (assume fastest 10m split of 0.9) and you increase your back squat to 400 pounds and your bodyweight to 200 pounds it's very likely that your 10m split will now be slower.
Note that this is less true for poorly trained athletes. If an athlete is running 13.0 seconds in the 100m then their max V may likely simply because they fatigue before they can accelerate to max V. If this is the case then overdistance work for endurance and increase in relative strength as measured by squat will increase their acceleration, maximum velocity and speed endurance.
Notice that this is less true for an untrained athlete.
Thanks for taking the time to answer this. Still, I don't understand your explanation. If an athlete increases his squat / bw ratio through an increase in bw and much larger increase in the squat, which mechanism makes that he is now slower?
i just don't get the ratio he used as in wasn't an increase in relative strength but rather absolute strength
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idk the times but at track last year, my starts were not so great, but i would end up catching up with everyone else. So i think for now i should only worry about getting my acceleration up. I max 275x1 full depth at 145 but i have a little bit of fat which i am takind care of.
Why cant i gain bw. I want to also get a good upper body physique for the ladies ;D ;D
I am going to work my way to squatting 295x5 from 200x5 i do now. That way i will have strong legs.
I clean instead of deadlift and i just cleaned 135x3 today and snatched 95x1 also.
WHat do you think about calf raises
NO ghr/reverse hyper...what about a back extension machine
If you want to be successful as a sprinter you need to know your times. Starts are largely technical. It's possible that you have poor starts because of technical flaws and you catch up to everyone else because you have superior acceleration. If you care about track you will care about your Max V because it ends up determining 95% of races. If you want to be a successful sprinter you should never aim to gain bodyweight.
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what about for sprinting>
Depends on whether you mean speed or actual sprinting. In general increasing your squat will help you more in two-footed standing jumping than it will in running. Squatting will usually have some carryover to the acceleration phase of sprinting. For speed relevant to sport (soccer, football, etc) this is about all that matters. However, for actual sprinting the acceleration phase is a minor part of the race. Most high level sprint races separate when athletes get the chance to display max velocity. The problem with this is that if your increases in the squat are combined with increases in bodyweight your maximum velocity may suffer EVEN if your relative strength (as measured by squat to bw) increases. If you plan on competing as a sprinter... watch out for this.
For a track sprinter, what would you prescribe to improve maximum velocity and how do you explain lower speed despite improved relative strength?
Maximum velocity is by far the hardest quality to train. It's equal part tendon stiffness and leg strength. For well trained athletes max V can be improved with overspeed work (pulling, slight downhill runs, etc), lot's of max V work (flying 20s, etc), single leg bounding work, or changes to mechanics.
It's lower speed despite improved relative strength as measured by the squat. You see this because the squat becomes a poor measure of strength at maximum velocity. Even high school sprinters have their fastest 10-meter splits well under a second. At this speed an athlete must exhibit extremely brief powerful single leg ground contact and the squat does not accurately predict their ability to produce power in this movement. So basically, if you weigh 150 pounds and squat 300 pounds and run an 11 flat 100m (assume fastest 10m split of 0.9) and you increase your back squat to 400 pounds and your bodyweight to 200 pounds it's very likely that your 10m split will now be slower.
Note that this is less true for poorly trained athletes. If an athlete is running 13.0 seconds in the 100m then their max V may likely simply because they fatigue before they can accelerate to max V. If this is the case then overdistance work for endurance and increase in relative strength as measured by squat will increase their acceleration, maximum velocity and speed endurance.
Notice that this is less true for an untrained athlete.
Thanks for taking the time to answer this. Still, I don't understand your explanation. If an athlete increases his squat / bw ratio through an increase in bw and much larger increase in the squat, which mechanism makes that he is now slower?
i just don't get the ratio he used as in wasn't an increase in relative strength but rather absolute strength
Sorry. Typo on the example. Assume the athlete is initially a 150 pound athlete squatting 300 pounds and becomes a 200 pound athlete squatting 450 pounds.
Anyway, the mechanism that makes him slower is the increase in bodyweight. At max V the squat loses its specificity to the relative strength the athlete needs to exhibit and no longer is a good predictor of performance.
For comparison we could instead look at vertical jump and three hypothetical athletes. All three athletes begin at 150lbs with 200 lb bench press, 300 lb squat and 400 lb deadlift. All three increase their bodyweight to 200 lbs to gain strength in one of the lifts. Athlete A now bench presses 500 lbs but his squat and deadlift are unchanged. Athlete B now squats 600 lbs but his bench and deadlift are unchanged. Athlete C now deadlifts 750 lbs but his squat and bench are unchanged. Which athlete is mostly likely to have increased his vertical jump? Most would answer B is most likely and A is least likely and C is somewhere in the middle. That's because the strength exhibited in the squat (not necessarily the lift itself - A VERY IMPORTANT DISTINCTION) is very specific to vertical jump, while the deadlift is less specific and the bench is the least specific. Athlete A did gain relative strength (as shown by bench) but most would not expect this to transfer to his vertical jump.
If you followed the previous example you can think of the relationship of achieving and holding max V and squatting as similar to the relationship between vertical jump and bench press or deadlift. This is why gaining weight is such a poor idea for sprinters.
The good thing is for clean athletes who don't go on stupid "bulking" diets you usually won't gain much more than 5lbs or so in a year. So for most non-elite athletes an increase in strength in any compound lift usually has a positive or at worst neutral effect on performance. When this is really a problem is when an athlete decides the need to "bulk" to gain strength and muscle and eats in excess and gains a large amount of fat, a small amount of muscle, and a moderate amount of strength.
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Sorry. Typo on the example. Assume the athlete is initially a 150 pound athlete squatting 300 pounds and becomes a 200 pound athlete squatting 450 pounds.
Anyway, the mechanism that makes him slower is the increase in bodyweight. At max V the squat loses its specificity to the relative strength the athlete needs to exhibit and no longer is a good predictor of performance.
For comparison we could instead look at vertical jump and three hypothetical athletes. All three athletes begin at 150lbs with 200 lb bench press, 300 lb squat and 400 lb deadlift. All three increase their bodyweight to 200 lbs to gain strength in one of the lifts. Athlete A now bench presses 500 lbs but his squat and deadlift are unchanged. Athlete B now squats 600 lbs but his bench and deadlift are unchanged. Athlete C now deadlifts 750 lbs but his squat and bench are unchanged. Which athlete is mostly likely to have increased his vertical jump? Most would answer B is most likely and A is least likely and C is somewhere in the middle. That's because the strength exhibited in the squat (not necessarily the lift itself - A VERY IMPORTANT DISTINCTION) is very specific to vertical jump, while the deadlift is less specific and the bench is the least specific. Athlete A did gain relative strength (as shown by bench) but most would not expect this to transfer to his vertical jump.
If you followed the previous example you can think of the relationship of achieving and holding max V and squatting as similar to the relationship between vertical jump and bench press or deadlift. This is why gaining weight is such a poor idea for sprinters.
The good thing is for clean athletes who don't go on stupid "bulking" diets you usually won't gain much more than 5lbs or so in a year. So for most non-elite athletes an increase in strength in any compound lift usually has a positive or at worst neutral effect on performance. When this is really a problem is when an athlete decides the need to "bulk" to gain strength and muscle and eats in excess and gains a large amount of fat, a small amount of muscle, and a moderate amount of strength.
Thanks again for your thoughts. I understand the reasoning now and want to comment on some of it and what it implicates to me as a layman in terms of track.
From what I understand you are basically saying that top end speed is the biggest determinant of success for a sprinter and at the same time responds the worst to training in general and responds probably not at all to increases in relative squat strength, except maybe for complete beginners, because it is that unspecific. You also give advice that a sprinter should never gain bodyweight because it slows down his maximum velocity. Assuming what was said initially was true for all cases I see no controversy regarding that argument. However it bears one of two implications that I will outline now:
A) If increases in bodyweight, no matter the composition of it, influences a sprinters V max and therefore his overall time that negatively, regardless of the squat specific strength gained in the process, than it logically follows that a decrease in bodyweight would have a positive influence on V max and his overall performance, regardless of squat specific strength lost during that process. UNLESS:
B) You for some reason assume that the bodyweight an athlete has is by some mechanism optimal and an increase OR decrease in bodyweight would both have negative influence.
Which one do you think is the case? If you believe A) is, then why are SOME elite sprinters not even lighter? Is Usain Bolt the lightest he can be at a competition weight of 190 lbs or could he be lighter and therefore [sic] faster? And if B) reflects your opinion, how can this be?
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Sorry. Typo on the example. Assume the athlete is initially a 150 pound athlete squatting 300 pounds and becomes a 200 pound athlete squatting 450 pounds.
Anyway, the mechanism that makes him slower is the increase in bodyweight. At max V the squat loses its specificity to the relative strength the athlete needs to exhibit and no longer is a good predictor of performance.
For comparison we could instead look at vertical jump and three hypothetical athletes. All three athletes begin at 150lbs with 200 lb bench press, 300 lb squat and 400 lb deadlift. All three increase their bodyweight to 200 lbs to gain strength in one of the lifts. Athlete A now bench presses 500 lbs but his squat and deadlift are unchanged. Athlete B now squats 600 lbs but his bench and deadlift are unchanged. Athlete C now deadlifts 750 lbs but his squat and bench are unchanged. Which athlete is mostly likely to have increased his vertical jump? Most would answer B is most likely and A is least likely and C is somewhere in the middle. That's because the strength exhibited in the squat (not necessarily the lift itself - A VERY IMPORTANT DISTINCTION) is very specific to vertical jump, while the deadlift is less specific and the bench is the least specific. Athlete A did gain relative strength (as shown by bench) but most would not expect this to transfer to his vertical jump.
If you followed the previous example you can think of the relationship of achieving and holding max V and squatting as similar to the relationship between vertical jump and bench press or deadlift. This is why gaining weight is such a poor idea for sprinters.
The good thing is for clean athletes who don't go on stupid "bulking" diets you usually won't gain much more than 5lbs or so in a year. So for most non-elite athletes an increase in strength in any compound lift usually has a positive or at worst neutral effect on performance. When this is really a problem is when an athlete decides the need to "bulk" to gain strength and muscle and eats in excess and gains a large amount of fat, a small amount of muscle, and a moderate amount of strength.
Thanks again for your thoughts. I understand the reasoning now and want to comment on some of it and what it implicates to me as a layman in terms of track.
From what I understand you are basically saying that top end speed is the biggest determinant of success for a sprinter and at the same time responds the worst to training in general and responds probably not at all to increases in relative squat strength, except maybe for complete beginners, because it is that unspecific. You also give advice that a sprinter should never gain bodyweight because it slows down his maximum velocity. Assuming what was said initially was true for all cases I see no controversy regarding that argument. However it bears one of two implications that I will outline now:
A) If increases in bodyweight, no matter the composition of it, influences a sprinters V max and therefore his overall time that negatively, regardless of the squat specific strength gained in the process, than it logically follows that a decrease in bodyweight would have a positive influence on V max and his overall performance, regardless of squat specific strength lost during that process. UNLESS:
B) You for some reason assume that the bodyweight an athlete has is by some mechanism optimal and an increase OR decrease in bodyweight would both have negative influence.
Which one do you think is the case? If you believe A) is, then why are SOME elite sprinters not even lighter? Is Usain Bolt the lightest he can be at a competition weight of 190 lbs or could he be lighter and therefore [sic] faster? And if B) reflects your opinion, how can this be?
Great reply. I will answer the A/B question but first I want to make some points to clarify some of those assumptions.
1) I should have said top end speed is the biggest determinant of success at a high level of track and field. If sprinters are not well trained they will lack speed endurance so much that this is not necessarily true. In fact in all sports except track and field (ie American football) what separates a "fast" from a "slow" athlete is acceleration. You could say that "sport specific speed" is acceleration. However, to see how this is true in track and field we can look at the all time marks. Even though the 60m is contested very rarely in comparison to the 100m there are a greater many more athletes who have run within reasonably close to the 60m world record. For example the high school 60m record is only 0.18 seconds from the 60m mark while the 100m high school record is 0.5 seconds from the mark. This discrepancy is why an athlete like Justin Gatlin can be meters faster than everyone in the NFL but still not become a great football player (his acceleration is only marginally better).
2) I should also have been clear about what a beginner is. By beginner I don't mean someone who does not run fast. Usain Bolt ran 20.5 seconds as a 6'5 170lb 15 year old. Unfortunately, that's faster than I have even run, and certainly not a time I would call beginner. He has since gained about close to 20 pounds and gotten much faster. So, in this definition he is a beginner. If you watch his 20.5 second 200m ( http://www.youtube.com/watch?v=T7W4kbobqIw ) you see a very weak but very fast athlete. The gains in strength he made to his upper-body, his back and abs and legs more than offset the additional weight. This wasn't necessarily increased squat strength but an overall increase in measurable strength.
Finally, as to whether it's A or B... I believe it's more A. Provided an athlete has "enough" relative strength to accelerate and hold their max V losing weight will be beneficial. In fact it's not well known but Usain Bolt actually lost about 10 pounds from 2010 to 2011. This is why I believe that had it not been for some injuries and an unfortunate false start Bolt was actually in his finest form yet. His split on the 4x100 was fastest of all time. If he can stay healthy I believe that the weight he has lost will be very helpful.
Of course the question you are asking is what is "enough" strength. It's something you can see on the track rather than in the weight room. For example Bolt does not have enough strength as a 15 year old, but today he does. Usually, a decent coach can make this assessment pretty quick when watching a track athlete. Of course, there are general guidelines that are decent suggestions for the weight room. For example if you can't do 10 pullups or you can't deadlift and squat far more than your bodyweight... You surely do not have enough strength and work in the weight room will help a lot. However, I hesitate to put a number on it.
Now, as to why I believe it could be B. Walter Dix. When I see an athlete like that I just can't imagine how he couldn't run much much faster if he lost 10-20 pounds. He carries a lot of muscle and much more fat than most sprinters. The only explanation I have heard is that we all have variable levels of bodyfat at which our leptin (a very important hormone) secretion is optimal. Leptin circulates in proportion to bodyfat and is one reason why nobody should aim to have extremely low bodyfat. When leptin is low you will not recover from training or perform well at all. So, it's possible that if an athlete like Dix has to carry an additional 10 lbs of bodyfat for adequate leptin secretion then he may as well carry an extra 15 lbs of muscle too to give him the required strength to weight ratios. Basically your level of leptin secretion will determine the size and strength that you need to be, somethin akin to the idea of finding your "ideal bodyweight".
*I hope that wraps it up. You might not believe my explanation for B, but if you do then that is why the advice is:
1) If you are light and strong, never gain weight to get stronger, because you will get slower.
2) If you are light and weak, get stronger. Ideally, attempt to do this without adding weight, but if weight is added it will be worth it. Don't do something stupid and deliberately get fat because you are on a "bulking diet".
3) If you are heavy and strong:
A) If you are naturally light (ie had you never lifted weights and bulked up you would be skinny) then losing weight will make you faster.
B) If you are naturally large (ie you have always had much more muscle and fat than average ) then you may not be able to lose weight because you require moderate bodyfat for hormonal regulation. Make sure never to gain weight to get stronger, but don't cut more weight than you are comfortable with.
4) If you are heavy and weak: Probably won't make a good sprinter.
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Uni-lateral Training: Fact and Fiction.
By Jim Wendler.
http://www.jimwendler.com/2011/09/uni-lateral-training-fact-and-fiction/