No slide.....huh?

[yahooyellow]

what do they mean that the world record 2k's have to be performed without a slide?

[johnlvs2run]

Slides are a couple of extra attachments that can be obtained for the erg to set on top of instead of the floor.

The advantage of this is that instead of moving the rower's weight back and forth, you just move the much lighter erg back and forth.

As this is easier, slides are not allowed to be used for record attempts.

[tditmar]

I do not believe John Rupp's GUESS is correct. It is based on his own faulty opinion of slides, which he has voiced over and over and over without a shred of proof (because it does not exist).

My own guess is that it is because the erg was static when the competitions started, and continued that way to maintain uniformity. Slides were "invented" later. Also, Concept 2 made the erg a sport and so the C2 erg is the erg used (not Rowperfect for example), and in a competition such as this were a computer monitor is measuring performance it makes sense to use the same apparatus (unlike say tennis where many brands of racquets can be compliant). If slides were used the "feeling" among competitors would be to be compared to others on slides vs static.

To address any advantage he thinks there is on slides, I bet if slides were allowed side by side, and the competitor had a choice, you would still see most of the top competitors using the static erg for the competition. In other words, when it gets down to it there is "no advantage," just a trade off. (For example, less control, especially at the start)

[johnlvs2run]

what do they mean that the world record 2k's have to be performed without a slide?

Here is more information about slides:

http://www.concept2.com/us/products/acc ... asp?bhcp=1

[Snail Space]

I do all my rowing on slides.
I absolutely love them.
But, you'll never see Snail Space on any WR honours boards!
[That's nothing to do with the slides]

[yahooyellow]

ahhh ok cool thank you, for second there i thought the seat would not have the ability to slide or something along those lines

[manos]

I do all my rowing on slides and I never think to go back training with out them,as you understand I am in love with the slides !!!!
Have a nice day
Regards from Greece

[tditmar]

Slides have made all the difference for me. The static erg was beginning to cause me chronic lower back pain, bought slides, lower back pain gone forever. In fact, I feel as though slides have strengthened my lower back significantly. And by the way, I never had issues with my lower back before buying the C2 without slides.

I hate to say it (because I get mixed feelings of disloyalty), but I have always been very curious about RowPerfect. I could see myself buying one of those down the road as they make their way into the US.

[xeno]

Hello Tditmar
I know exactly how you feel.
I have used Concept2 since my very first days of rowing back in 1985. Before using the slides, I did not know any better. Then in 2001, I bought slides from my friend Dave from Huntington beach and I loved it, because I was able to watch TV without having to refocuse all the time.
A couple of years later when I figured out that international rowing competition was not good for my stress and income, I decided to start our indoor rowing studio, IRON OARSMAN.
There is absolutely NO WAY in heck that I would have dared start the business without slides. A few of the rowers at the Iron Oarsman travel for business and find Concept2 machines without slides at hotel gyms and they are shocked what a difference it is to row on a static rower.

I would like to repeat: I have enjoyed the costumer support from Concept2 always. The machine is very well made. However, on a business level I never fit into Concept2 grand plan. This is why I found ROWPERFECT. It turns out that the man owning the company is one heck of fun man. His name is Mark Campbell. He is a rower himself and his wife went to the Olympics in rowing. They have five children and he is a pet vet. I hit it off with him so fast, it was just great.

I am a key person for the testing, because we, at the Iron Oarsman, are going to heavily use the early machines. Trust me, if I am banking my future on a rowing machine I am going to try to beat the living heck out of it. I am abslolutely certain that the machine will be bullet proof.
The size of the machine is considerably smaller than the Concpet2 with or without slides. The Rowperfect will fit in a suitcase similar to a back carrier. This means it can fly anywhere on a passenger jet.
For closing I would like to repeat that through my work with ROWPERFECT I feel a certain break from the Concpet2 world of indoor rowing.
I remember inviting Dick Dreissigacker (co founder of C2 with his brother Peter) to come talk to our business class at Brown. Dick graduated from Brown. I remember feeling really proud to have a fellow rower stand infront of our class.
Now I need to fight for my family's future and I want to grow indoor rowing throughout the world, because we all know on this board what an amazing exercise rowing is. Rowing is arguably one of the VERY FEW sports which does not discriminate by age and fintess.

Sincerely, XENO
P.S.
Happy Valentine's Day.

[chgoss]

Hi Xeno,
Couple questions for you regarding slides:
1) what is the real benefit of training on slides? I have a bad knee for example.. after I do a really hard interval session at a high rate, it aches.. Are slides less of an impact on joints than non-slides?

2) In your experience, is there really any difference in times on slides vs not?

3) do you know of anyone that trains on slides and competes at any of the indoor venues? Is it difficult to switch back and forth (slides/no slides)

thanks for any input you might have!
-chad

[johnlvs2run]

The slides are great, and much easier to use than the stand-alone erg. With my limited use of them my times are 1.5 to 3 seconds per 500m faster on the slides than the erg. A heavier person would find a greater differential with the times, with the advantage to the slides. It's important to keep the same distance per stroke when rowing on the slides as the erg. Some people change this a lot on the slides and then apparently lose time because of it.

I sold a model C last summer and was looking into getting a rowperfect at that time. In fact, I had decided to get one.

I contacted rowperfect several times, told them I was interested to buy one, wanted to do it and asked how and where I could get one.

Well they never answered me.

In the meantime I read some links about rowperfects in clubs with signs that they couldn't be used without supervision because they didn't hold up well to usage. That caused me to evaluate my decision. As rowperfect was not able to get back to me in a timely manner, they apparently didn't have any ergs ready to sell anyway, and never did give me a price for one though I think they were in the range of $3000 - quite pricey - and concept2 is always at the top of their game as to having ergs ready and great customer service, instead of a rowperfect I invested in a new model D/pm3.

Since doing so, there have been a few glitches like a shimmy and not happy with the pm3 but overall I am pleased with Concept2, the quality of their machines and their service.

Rowperfect might be along some time in the future, but in the present they can't hold a candle to Concept2, a concept2 erg, or a concept2 erg on the slides.

As to the slides, it would be nice to see a category for times with them in the rankings. C2 was talking about including this a few years ago but hasn't gotten around to it yet. Based on this my guess is that they probably wont. In the meantime I only enter erg times in the rankings, though both are allowed, because my slide times are so much easier and faster. I'd estimate my 2k is from 10 to 15 seconds faster on the slides.

Oh yes, a few months after purchasing a new model D, rowperfect did get back to me. They sent an article about something obscure but that had nothing to do with my question on how I could buy one. In the meantime they convinced me that I didn't want nor need one of them anyway.

I highly recommend the concept2 slides for training.

If you're thinking of getting a rowperfect though, good luck and don't hold your breath.

[xeno]

Hello Chad,
Great to hear from you.
At the beginning of this post you will find my answers. Then you will find a research paper that compares dynamic versus slides.
"Rowing" on slides is more like rowing on the water. Because the mass of the rower is greater than the rowing machine on slides, the machine does most of the back and forth movement. This in turn lightens the load on the lower back at the catch and finish. Similarly the compression of the knees when using the slide is the result from actively contracting the hamstrings. Unlike rowing the stationary rowing machine, when rolling into the catch, the body weight compresses the knees, overcompressing is very likely if not coached otherwise.

Is there a difference in speed with slides. The shorter the distance the greater the advantage with slides because the rower can rate much higher than when rowing a static set up. However if you row 1000 meters and up, the slides do not have a real advantage. The rowing stroke is slightly shorter on slides if the athlete is not paying attention to keeping the stroke long.

Robert Waddell who won the Olympic gold when I got the silver in 2000 was several time world champion on the Concept2 machine. His main training of the water was done on the rowperfect. If you are fit in rowing on the water you will be fit to row a good score on either indoor rowing set up. However, if I were to chose to compete an indoor rowing regatta I would stop using the sliders a month ahead of time to get my body tuned to the rowing movement with a stationary rowing machine.

The good thing about the Rowperfect is that it takes into account body weight when calculating actual rowing speeed. In order to compare C2 speed to Rowperfect speed, one has to dial into the ROWPERFECT men's 4- weighing 220 pounds or 100 kg.

It is not difficult to switch back and forth. It is a particularly funny sensation to row a stationary erg when you just completed an entire workout on slides.

I understand Concept2 for not advertising dynamic rowing because it requires more equipment to enjoy rowing. The customer's ignorance about rowing is Concpet2's bliss. I don't know how much longer this will last because of individuals like me and research papers such as the one below.

I have no doubt that Concept2 can improve their product to make it "dynamic". The only road block they face is that all major patents belong to ROWPERFECT.

Please find the research below.
All the best,
XENO

A Discussion of Fixed vs Dynamic Ergometers – Ivan Hooper*
Since I sent out some comments regarding ergometer use, I have had quite a few emails back regarding the use of the Row Perfect ergometer, or putting the Concept II ergometer on sliders. I am aware that there is some work underway investigating this issue, but currently there are not a lot of papers that have been published.
In working through some of the literature I came across a website that goes some way towards explaining the physics of ergometer rowing (Dudhia, 1999). It discusses that a fundamental difference between the linear mechanics of a ‘static’ ergometer (such as a Concept II) and a boat can be illustrated by the following test:
If you sit at front-stops on an erg and then push your legs down you move backwards relative to room by an amount equal to your leg length
If you sit at front-stops in a single and then push your legs down (oars out of the water) you only move backwards relative to the bank by an amount ~20% of your leg length - the rest of the motion is taken by the boat moving away from you.
This is a result of the action-reaction principle (Newton's 3rd Law). The force applied by your legs to the stretcher acts equally on you and the stretcher. In the static case (ergometer), the stretcher is effectively attached to the whole planet so doesn't move - you do all the moving. In the dynamic case (boat), the mass of the single scull is much lighter (typically 10-20%) than you, so it moves further than you do.
This is not just a matter of the frame of reference: in the static case (ergometer) you are actually performing more work accelerating your whole body weight up and down the slides, thereby creating high levels of kinetic energy. In the dynamic case (boat) your body weight is relatively stationary, creating much lower levels of kinetic energy and thus requiring less work to be done to reverse this kinetic energy. It results in an athlete needing to put in six times more energy just accelerating and decelerating their own body weight, compared to on water rowing.
A ‘dynamic’ ergometer, such as the Row Perfect, attempts to simulate the mechanics of on water rowing by having the stretcher/flywheel also mounted on a rail. Attempts have been made to simulate the same effect by mounting the Concept II on sliders.
Most of the literature that I have read was performed examining the Row Perfect ergometer in a mobile and fixed state. The weight of the Row Perfect mobile power head is approximately 19kg, which is not that dissimilar to the weight of a single scull. This is the weight that an athlete’s leg drive is moving every stroke. Hence the manufacturer’s claims that the mechanics of the Row Perfect and on water rowing are similar.
The weight of a Concept II is nearly 28kg. When you include the mobile component of the sliders, the weight is around 35kg (or 39kg for the newer Model E). If you consider the mechanics discussed earlier, when a Concept II is mounted on sliders there would be more motion of the rower and less motion of the ergometer when compared to the Row Perfect. Hence, my thinking is that sliders probably go a long way to replicating the mechanics of on water rowing, but still involve forces nearly double that of the Row Perfect.
There are two recent papers that have both described the mechanics of static versus dynamic ergometers, using the Row Perfect in both a dynamic and fixed state. Bernstein et al (2002) found that average stroke length on the static ergometer was 53mm longer. They discussed that this is due to the higher kinetic energy associated with moving the whole body mass, as was discussed earlier. Colloud et al (2006) also discussed the higher inertial forces generated during the transition between the recovery and propulsive phases, especially at the catch.

This kinetic energy, and / or inertia, has to decrease to zero for a change in direction to occur, thus something has to exert or absorb forces. Coming forward this force is absorbed by passive tissue structures of the knees resulting in an 8-10% increased leg compression (Kleshnev, 2005). It is reasonable to assume that the lumbar spine also absorbs some of this kinetic energy, creating an increase in lumbar flexion. Holt et al (2003) supported this when studying the effects of prolonged ergometer rowing. Over a 60 minute piece there were significant increases in the lumbar spine range of motion at the catch and total lumbar spine range of motion.

At the finish it is the large hip flexors that act to decrease and reverse the kinetic energy of the trunk (Rekers, 2006). This places very high loads on the lumbar spine, equivalent to doing prolonged sit ups. This places large sheer forces across the structures of the lumbar spine, potentially contributing to injury (Stallard, 1994).

Both Bernstein et al (2002) and Colloud et al (2006) found higher maximum stroke forces and power when using the static compared to the dynamic ergometer. They suggest that the passive structures of the rower’s joints could be loaded more at the catch on the static ergometer when the lower limb joints and trunk are fully flexed. They both propose that these higher forces, imposed over a longer stroke, may be associated with injury.

Undoubtedly, higher forces applied over a longer distance means more work done by the body’s muscles. More work done means earlier fatigue. Fatigued lumbar spine muscles may allow even more lumbar flexion, transferring higher forces to the passive tissues of the spine. The combination of lumbar flexion and muscular fatigue has long been identified as a cause of lumbar spine injury amongst rowers (Reid & McNair, 2000).

After repetitive motion, protective muscle activity has been shown to be reduced, often for a number of hours after the exercise is completed (Gedalia et al, 1999) The ramification for rowers is that, during this period, the athlete may be more vulnerable to injury, even when they may not be experiencing high loading on the spine (Reid & McNair, 2000). Ergometer use and weight training are two modalities that are likely to load the trunk muscles more than on water rowing. Based on the findings mentioned above, placing these two training modalities in close proximity is likely to increase injury risk.

In discussing ergometer versus on water rowing, Kleshnev (2005) noted several differences. He stated that the legs execute more work on a stationary ergo, but in a slower static motion. On the water the legs work much faster at the catch, when the force is not very high and therefore execute less power. In this aspect a dynamic ergometer stands somewhere between a stationary ergometer and on water rowing.

This may be an aspect that coaches wish to utilise if they are looking to enhance leg training, but I question the value of this when the load and contraction speeds are significantly different to on water rowing. The other issue is that once the legs fatigue, the trunk then becomes a greater contributor to total work performed. As mentioned above, this leads to a fatigue of the trunk muscles, placing lumbar spine structures at higher risk of injury.

In conclusion, the information that is currently available supports the idea that ergometer use is a risk factor for lumbar spine injury. It also suggests that the Row Perfect places much lower detrimental forces on the rower than the Concept II. It seems that placing the Concept II on sliders is also a way of reducing these detrimental forces, but this is probably not as effective as the Row Perfect.

At this point in time, the Concept II is the standard for conducting physiological testing of the elite rower. I do not propose that this change immediately, but I do think that what machine we test on in the future needs further examination and evaluation. Issues such as injury risk and physiological specificity need to be considered when selecting the most appropriate way to test our athletes.

In summarising the information that is currently available regarding ergometer use and its effects on injury, I would like to make the following recommendations:

· Reduce the volume of work done on Concept II ergometers in the stationary setting.

· Keep the maximum length of a piece on an ergometer less than 30 minutes. If more than 30 minutes is to be done in a session, make sure that the session is broken up into shorter pieces with appropriate rest and stretching in between the pieces.

· Where appropriate, use either the Row Perfect or Concept II ergometer on sliders.

· Where appropriate, use other forms of cross training. Consider using cross training in conjunction with ergometer training in order to achieve the necessary training volume.

· Endeavour to place ergometer sessions and weights sessions on separate training days, or at least several hours apart.

· Provide good supervision of technique while athletes train on an ergometer. The level of attention to technical detail on an ergometer should be no different to when training on water.

· Ensure that athletes understand that the need for good technique while training on an ergometer is as important as when on water.

· Be aware that some people will never have problems on an ergometer, while others may have significant problems. Coaches should be prepared to individualise training programs to suit each athlete.

The recommendations made in this article are based on a balance between possible injury risks, and the acknowledged benefits of ergometer training. Ideally these recommendations are designed to stimulate thought when devising training programs. I would encourage coaches to consider both the potential benefits and the potential risks of all forms of training.

Finally I would like to remind everyone that coaches have a duty to make their crews as fast as possible, without causing damage to the people for whom they are responsible (Stallard, 1994). An ongoing challenge for all coaches is to minimise the potentially detrimental aspects of their training programs.




References

Bernstein I A et al (2002) An ergonomic comparison of rowing machine designs: possible implications for safety. British Journal of Sports Med; 36:108-112

Colloud F et al (2006) Fixed versus free floating stretcher mechanism in rowing ergometers: Mechanical aspects. Journal of Sports Sciences; 24: 1-15

Dudhia, A (1999) The physics of rowing: dynamic versus static ergometers. http://www.atm.ox.ac.uk/rowing/physics/index.html

Gedalia U et al (1999) Biomechanics of increased exposure to lumbar injury caused by cyclic loading. Part 2. Recovery of reflexive muscular stability with rest. Spine; 24: 2461-7

Holt P J E et al (2003) Kinematics of spinal motion during prolonged rowing. International Journal of Sports Medicine; 24: 597-602.

Kleshnev V (2005) Rowing Biomechanics Newsletter; Vol 5: No 1

Reid D A & McNair P J (2000) Factors contributing to low back pain in rowers. British Journal of Sports Med; 34:321-325

Rekers, C (2006) Personal Correspondence.

Stallard, M (1994) Regatta; 66, p22.


Author:

Ivan Hooper M.Phty.St (Sports Phty), B.Sc (HMS)
APA Sports Physiotherapist
Australian Institute of Sport

Rowing Australia
Sports Science / Sports Medicine Coordinator

PO Box 176
Belconnen ACT 2616

F: 02 6214 7953

Ivan.Hooper@ausport.gov.au

[johnlvs2run]

I'm not trying to interfere with the advertisements but want to give some more information on the slides.

Warren Berger turned a model B into a dynamic erg a few years ago, with fixed seat, moving foot plates and fan in back, which was much more stable than the regular model B erg. He told me he contacted c2 and felt they weren't interested in a dynamic erg at that time or in working with him to develop one. I offered to purchase a kit or the plans for conversion but he said it wasn't all that easy to do.

What I'd like to see is that Concept2 would get together with Warren so they could develop a plan for a dynamic Concept2 erg. In my opinion, by doing this and with Concept2's marketing network, they could be so far ahead that rowperfect would never have any chance to catch up.

Also this would be a major advance in the dynamics of the Concept2 erg.

Somehow I think that Concept2 would love to have their ergs be dynamic, and this is a way they could accomplish this objective.

Here is Warren Berger on his dynamic model B erg:

http://www.rowvelo.com/images/p1.jpg

http://www.rowvelo.com/images/p2.jpg

http://www.rowvelo.com/images/p3.jpg

I had a video of him rowing on it somewhere but am not sure where it is.

[chgoss]

Xeno,
Many thanks for the data, I will read it carefully.

I live in Boston, travel to San Jose a lot.. One of these days I am going to make the extra hop and get down to Costa Mesa for a Saturday lesson

best
-chad

[lt_gustavsen]

I’m interested in slide my self and I found this page very interesting.
http://www.mosmanrowing.com/news/2007/0 ... rgometers/

Regards
Lars