The Doctor

I think one of the biggest problems this year is that the juniors have been made to race with the elite riders. A lot of the younger junior's are out of their depth and are struggling to keep with the pace of the elite riders, leading to mistakes and wild attempts to stay in the group. It is also important to distinguish between the junior Acsis team and the elites. The elite riders have been coached, trained and skilled at the Sports Science Institute for the last 14 months and it shows. They attend a weekly briefing, training and monitoring session. They are doing field training sessions and laboratory training. In fact, no Acsis ELITE rider has been involved in a single crash since the Giro last year. There were four big crashes at the Construction Du Cap 99er and not one involved an Acsis rider, yet I don't see a single post about any of those crashes. I agree that the juniors are very erratic and need to be skilled but some of these guys are only 16 and have been riding for months, not years. They should not be riding with the elites. Next time one of the riders causes a crash, take down his number, complain about the specific rider to the race organisers and to the specific team manager (different for elites and juniors). In essence, stop painting everyone with the same brush.

No Biopsies. Just a few little blood samples and a lot of suffering on the indoor ergometer! Sorry. Forgot to mention it is a men's trial.

This is a really good opportunity to get a comprehensive testing and do some really hard riding in a controlled environment. Never mind the bike fit - There is a 2 month waiting period if you don't do the trial!

This is a really good opportunity to get a comprehensive testing and do some really hard riding in a controlled environment. Never mind the bike fit - There is a 2 month waiting period if you don't do the trial!

Dear Cyclist We are currently conducting a research trial at SSISA. If you are interested in participating, please see the attached information sheet and criteria below: Present in Western Cape / Cape Town Age 18 - 45 years No orthopaedic problems which may interfere with trial performance or results. No recent illness, hospitalization or surgical procedures No chronic conditions requiring medication that might alter metabolic responses to exercise and exercise performance i.e. thyroid abnormalities, uncontrolled asthma, cardiovascular conditions, diabetes, impaired glucose tolerance and high blood pressure. At least 3 years training history with an average cumulative training time of at least 6 hours each week Preferably available for 1.5 hours on Tueday or Wednesday evening and available on the following morning for main component of trial for 4 hours (earliest start time 5am). We will consider a Friday or Saturday evening and the following morning 4 hour session on Sat. Sun. if not available during the week. Benefits: Dr Jeroen Swart to provide for free: Full physiological testing results and interpretation. 8-12 week personalised training program. Comprehensive bike fit. Worth approx: R2500 Please contact me at jeroen.swart@uct.ac.za

JB when last I checked, this was a forum and not a peer reviewed scientific journal. I think it is entirely appropriate for me to use adjectives to describe my opinion. Likewise, your statements are also opinions (however misguided they may be). The front tyre contact patch is the area of the tyre which is in contact with the road surface after deformation of the tyre. In addition to friction co-efficients, the angle of forces acting on the contact patch determine when the tyre will break free. In addition, the fork offset and seat tube angle affect the lateral loading of the tyre sidewall during cornering. At low tyre pressures and high tyre volumes (such as on a mountainbike), this can be a signifcant factor affecting the grip levels and handling. The position of the rider with respect to the front wheel determine the angle of forces exerted on the front tyre contact patch. Without going into a protracted discussion about how each variable affects the bike's handling, suffice to say that your use of technical jargon is an attempt to intimidate individuals on this forum who may not be able to respond in kind. I have watched your posts for a while now and they are all very similar. They try to portray opinion as fact. The truth however, is very different. If you are confident of your opinions, please write them up and publish them in an appropriate journal, not a magazine article. We might then start to take you seriously.

JB - Perhaps you should spend less time tinkering and a little more time riding. Previously you spouted forth that V-brakes are just as effective as disc brakes, now you claim that wheelbase, head tube angle and top tube length do not affect handling characteristics! With respect to top tube alone, in line with this post, the top tube length and stem length in combination with setup together determine the front contact patch loading. On a mountainbike this has a fairly dramatic effect on handling. The same applies to road bikes but requires that you ride at some speed into a corner to notice the difference (Leave the panniers at home). Likewise, head tube angle, wheelbase length and bottom bracket height (which varies considerably on mountainbikes) can make a huge difference. This applies to ordinary cross country bikes being ridden on different terrain and not for downhill bikes and unicycles.

There are a number of advantages to disc brakes that cannot be overcome with rim brakes: A disc can exert a greater mechanical advantage due to two factors. 1) the lateral runout of the disc has tighter tollerances than a rim, allowing the disc to have a very high mechanical advantage without the presence of accidental brake scrub. The greater diameter of the rim and the fact that it is a load bearing structure of the wheel result in lateral forces causing movement. The manufacturers of rim brakes need to keep the mechanical advantage smaller so that the brake blocks retract far enough to allow the lateral movement of the rim. This is not the case in disc brakes. 2) The hydraulic fluid has vitually 0 friction and therefore there is very little loss of force between the lever and the brake caliper. A well maintained cable brake will be similar but will not remain that way, unlike disc brakes which are virtually maintanance free. Human skeletal muscle fibre unit sizes are recruited in relation to the force needed. If the forces are low, there is recruitment of small muscle fibre units in which a single nerve supplies each muscle fibre. As the force increases, the number of fibres per nerve increases, decreasing the fine motor control. The result is that under high force situations (panic braking and off road) the ability to modulate the brake is lost with low mechanical advantage systems. Similarly, disc brakes provide greater control during riding in comparison to most cable operated rim brakes. It is also quite apparent that a lot of the posts on this thread have been made by people who have not ridden a mountainbike in technical terrain with V-brakes and then disc brakes. If they had, they would not ask whcih was better. Finally, with respect to wet conditions, the rim is simply closer to the ground and therefore picks up a lot more mud and dirt. When it is really muddy and wet, this results in a delay in the application of braking force that does not occur with discs (which remain fairly clean).The Doctor2008-09-30 14:02:35

Bruce - Where did you get all this info? It seems like Saris has been very tight lipped about this.

Manufacturers spend countless hours each year redesigning and perfecting the position of the pick up ramps, pins and gates so that our shifting is as smooth as a babies toosh. Unfortunately your design will move these out of position and affect the shifting negatively.

Rocket man: To determine whether a result is statistically significant, there are a number of factors that are taken into account. Two important characteristic in biological systems are the within subject variability and the measurement error of the ergometer you use. The within subject error varies depending on how tightly controlled the testing conditions are. We conducted a study last year where subjects were asked to perform a VO2max test and 40km TT at weekly intervals for 5 weeks. They were blinded to their performance and therefore could not pace themselves. The variation in test performance in this type of study is a combination of measurement error within subject variation. It therefore provides a practical value to gauge changes over time. The co-efficients of variation (standard deviation / mean) for both tests were less than 1%. Previous research has shown that a change of approximately 1% is a meaningful difference in cycling. A change in performance paramater of more than 2% is therefore significant (1% with 1% varation = 2% to be sure that the result is meaningful) The questions that you are posting are making the assumption that the research is conducted in a Micky mouse fashion. We consider and control for nearly every possible variable during the research. Only then can you be sure that what you are seeing is in fact correct. I won't respond to each individual question as my fingers are starting to bleed from all the typing. Peter: We have done lots of Central governor studies using perceived exertion. There is about a 10min lag in RPE which makes it fairly impractical for use in interval training.

There are a lot of elite athletes who use "traditional" training methods and shun new technology. It begs the question whether they would be even better of they did things scientifically. To win Roubaix: Ride 6 hours each day behind the motorcycle Eat pea soup mixed with mud and cow dung Live in Belgium and drink lots of Belgian beer Get an old, wrinkled, skinny soigneur to rub your legs all day Rub spirits on your butt to turn the skin into leather Get a 16 year old girlfriend and pretend that you're dating her because she's really "mature"

This debate is not on whether buying a power meter is a good investment. If you are looking to maximise your training then a power meter is going to help you achieve that aim. The debate is about the prescription of training intensity. You can prescribe heart rate, power, RPE, speed etc. Of these power is the most accurate measure of work performed. BUT Is it always best to be accurate? This seems like a mute question but the answer is surprising!

Peter That is exactly what happens with research. You start out by wanting to answer one question and you end up with a whole nest of questions that require more research. The simple answer is that if you are going to do an 8 x 4min session at above LT then it is easier and more effective to do the session based on heart rate. If you are going to do a T-max session then you use a target power. If you do a blowout session then you use a target power. If you do any other session then toss a coin for now. It is important not to adopt a position when some new technology arrives that you throw out the previous technology and make the automatic assumption that the older technology is inferior in every sinlge aspect. You need to establish the rules by scientific validation and then move forward.

24.38% greater. Remember that they were equaly lower by the end of the interval as well. Hence - Same averge, different power curve, better training stimulus.

Now you are talking.. Half life for HR around 26 secs (If I recall correctly) would mean about 2.5-3 mins for HR to level off. While attempting to achieve target HR the subjects would have been at a level closer to Vo2 Max and so maybe spent more time at or around this zone - leading to a greater increase in Vo2 ? Exactly!

Now you are talking.. Half life for HR around 26 secs (If I recall correctly) would mean about 2.5-3 mins for HR to level off. While attempting to achieve target HR the subjects would have been at a level closer to Vo2 Max and so maybe spent more time at or around this zone - leading to a greater increase in Vo2 ? Exactly!

Now you are talking.. Half life for HR around 26 secs (If I recall correctly) would mean about 2.5-3 mins for HR to level off. While attempting to achieve target HR the subjects would have been at a level closer to Vo2 Max and so maybe spent more time at or around this zone - leading to a greater increase in Vo2 ? Exactly!

Now you are talking.. Half life for HR around 26 secs (If I recall correctly) would mean about 2.5-3 mins for HR to level off. While attempting to achieve target HR the subjects would have been at a level closer to Vo2 Max and so maybe spent more time at or around this zone - leading to a greater increase in Vo2 ? Exactly!

The heart rate intervals are recorded based on the time and not on the actual heart rate. Heart rate lag is about 3min. for the first interval falls to less than 45s by the third interval.

Rocket Man 4 minute intervals have consistantly imrpoved VO2max and PPo by between 3 and 6 percent over a 4-6 week period. There are about 6 different studies that have proven this. The fact that they are doing short bursts of "supra-maximal" training at the start of each interval is the reason that we summised that they improved to a greater extent than the poewer group. By the way, the improvement in 40km TT time was the same for both groups 2.1% vs 2.3%. Peter - Using a power band would have restricted the maximum power in the early part of each interval, something that didn't happen in the heart rate group. Remember that this study only applies to that particular type of session. Someone out there needs to do more research for LT type sessions to see whether staying in a power band is providing more benefit or whether "preloading" the interval to get the heart rate up is going to provide a greater training stress or impulse. Training studies are time consuming and exhausting (not just to the athletes)

Sorry Peter Its difficult to gauge the tone in the written form. Feel free to ask questions at your leisure.