Thursday, May 10, 2018

Fatigue and How It Impacts Range of Motion in the Foot



By PCG Master Coach Hunter Allen

This past month, I was able to gather motion data on many of the cyclists that came to our 21st annual cycling camp here in the beautiful Blue Ridge Mountains. The main goal was to be able to identify when a rider fatigues based on a change in their motion. This could be the motion in their foot angular range (how far the foot moves up and down), or in their torso movement, which includes rotation, angle, and rock. Fatigue and movement are fickle things, and sometimes hard to identify. Some riders will change the way their feet move when they become tired in a ride, and others will move their upper body more.  The calf muscles (gastrocnemius) hold their foot in place when pedaling, and for many riders, when they fatigue, they are no longer able to hold the foot within the previous range of motion.  For some riders, this means reducing their range of motion, for others, it means increasing it. Many riders will also change their upper body movements when they become fatigued, and 99% of the time, they will increase their torso rotation, or rock, and even change the angle of their torso. With this in mind, we looked at all of the riders using a LEOMO TYPE-R at the camp to see if we could identify fatigue from a big picture view.

Our first rider completed the “long” day at camp, which is 95 miles over two mountains, each mountain stretch being about 35 minutes long. He had no change in his foot angular range throughout the entire ride. However, when I compared the ride after the first climb (while he was still fresh) to the ride after the second climb, then there were some big changes in his torso data. First off, he was no longer able (or willing) to keep his upper body as low as he could when fresh, so he was less aerodynamic at the end of the ride than at the beginning. Second, he rotated his body more in the second half of the ride versus the first half, which is a well-known indicator that a rider is fatigued and needs to use their upper body more to help with the pedaling motion.  



In our second rider, we see an increase in the FAR, foot angular range, near the end of the ride as he fatigued. This rider’s feet moved more once he became fatigued. I believe the reason for this is that his calf muscles were so tired that he could no longer hold his foot in it’s normal position, and could no longer hold his foot stable. 





Our next example is yours truly. In our long ride, we have two mountains that we must climb up and over. On the first climb, I was relatively fresh and felt good the entire way up the climb, but, from Figure 3, you’ll notice that my FAR became larger and larger near the end of the climb. I attribute this to accumulated muscular fatigue over the week of riding. For the second climb, you’ll notice, also in figure 3, that the opposite happens, and my FAR becomes smaller over the climb. Even though I was more fatigued on this second climb, the climb itself also becomes less steep the closer you get to the top. I believe that I was climbing very steadily during this time, and that reduced my FAR. The two long green dashed lines in Figure 3 show that the overall FAR continued to increase throughout the entire ride, which demonstrates increasing fatigue and how it impacts motion.



Why is this so important to be able to see fatigue? If we can see where fatigue occurs, then that gives us more insight into the endurance and stamina of the athlete. This will allow the rider or coach to make important decisions about the upcoming type of training needed for the athlete. (More on how and what decisions to make will come later in another article.)

Tuesday, May 8, 2018

How To Spend Your Cycling Money


By PCG Coach David Ertl


A study by Asker Jeukendrup and James Martini examined the literature for the benefits of different interventions on time trial performance.  The paper used a formula to predict the size of the effect of these interventions based on the results of studies published in peer reviewed literature.  Those interested in the mathematics of the model should seek out the journal article.  The authors separated riders into three categories:  novice, well-trained and elite.  The absolute savings for the better riders is less since they are going to be on the course for less time.  The percentage improvement for the groups would be similar.  The authors also chose the TT since a mass start race brings into play team tactics, skills, experience, etc that cannot be quantified.  The TT, while involving some strategy and skill, is less “polluted” by these factors.
Studies show that well-trained cyclists ingesting a carbohydrate beverage improved 40km TT time by 2.3% compared to a placebo (in this case a beverage not containing carbs).  Over a one hour period, average power would be increased by at least ~2%.i
 According to a formula developed by one of the authors, a novice (N) cyclist would improved his/her 40km TT by 42 seconds; a well-trained (W) cyclist would improve by 36 seconds; and, an elite (E) cyclist would improve by 32 seconds. 
            The authors’ analysis reviewed caffeine ingestion and determined that this intervention would increase power by 5% thus leading to an improvement in the 40km TT of 84, 63, and 55 seconds for the N,W and E cyclists, respectively.i 
            How about spending money on a lighter bike?  Cyclists love to spend money on lighter and the latest parts.  The authors examined the effect of reducing bike weight from 10kg (~22 pounds) to 7kg (~14.5 pounds) on 40km TT performance.  The effect is the N, W, and E cyclist improves by 13, 7 and 5 seconds, respectively.i  Along those lines, losing 3 kg of body weight would reduce drag area by 1.84%.  This reduction would improve 40km TT performance by 25, 21, and 19 seconds for the N, W, and E cyclist respectively.
            What about going uphill?   Wouldn’t a lighter bike and/or weighing less make a difference?  Of course!  It is nice when science supports what we think to be true. On a 3% grade on a 20km TT, the authors determined that reducing bike weight by 3kg would result in a time savings of 94, 42 and 29 seconds for the N, W, and E cyclists.  Increasing the grade to 6% yields savings of 3:38, 1:52, and 1:15 for the N, W, and E cyclists, respectively. i 
(Note: Since most athletes at a given level have the same equipment (and UCI rules set a minimum bike weight), once you get as light as you can, the advantage in terms of placement in competition diminishes.  It could be argued that the lower category riders benefit more in terms of standings since they are more likely to be competing with athletes who have entry-level bikes. 
I doubt the weight of Lance’s TT bike is all that different from his main competitors.)
How about spending some time in a wind tunnel to improve my TT performance?  The authors report that optimizing aerodynamic position can lead to a performance improvement by 2 to 2.5 minutes compared to a “baseline” measure of the rider with elbows on TT handle bars.
Surely buying the latest aerodynamic frame would make me a World Champion.  (Sarcastic comment:  Only if you were the only athlete with one and only if you had the engine to become a World Champion!)  The savings for N, W, and E cyclists with the aero frame compared to a conventional frame (steel round tube) was calculated to be 1;44, 1:26 and 1:17, respectively.

The charti below summarizes the information above.

Time savings in Time Trial Performance.  All are 40km TT except where noted. Time is expressed mm:ss.

Novice Cyclist
Well-Trained Cyclist
Elite Cyclist
Carbohydrate Beverage Ingestion
0:42 
0:36 
0: 32
Caffeine
1:24
1:03
0:55
Lighter Bike (flat TT)
0:13
0:07
0:05
Lighter Bike (uphill TT 3% grade, 20km)
1:34
0:42
0:29
Lighter Bike (uphill TT 6% grade, 20km)
3:38
1:52
1:15
Aerodynamic Positioning
2:00-2:30
2:00-2:30
2:00-2:30
Aerodynamic Frame
1:44
1:26
1:17

How about training?
            The authors report that 9 to 12 weeks of training leads to improvement in VO2max by 20 to 38% in several studies using untrained subjectsi.    In moderately trained cyclists (average VO2max 57 as ml-1kg-1min-1 ) at the beginning of the season), the authors report on a study by
Norris and Petersen of 8 weeks of training (5 sessions per week, 40 to 55 minutes per session). 
Within 4 weeks performance was improved; at the end of 8 weeks, VO2max improved by 5% and 40km TT performance improved by 8.4%.  The authors report other studies using a variety of training interventions that lead to a performance increase or an improvement in laboratory measurements.  It should be noted that many factors go into the magnitude of the improvement such as VO2max at the onset of training (the lower the value, the greater the potential increase) and the volume, intensity and duration of training involved.
            Jeukendrup and Martini estimate that N, W, and E cyclists can improve 40km TT performance by proper training; the table below from the Jeukendrup and Martin paper shows the estimated effect of training on 40km TT.  The authors estimate that proper training including high intensity intervals and sustained endurance can improve novice performance in the TT by 5 to 10%; modifying the training program for well-trained riders yields a 2 to 4% improvement;  elite cyclists, since they are already so highly trained, improve by 1 to 3%.  Of course, a difference of 1% or less in the Olympics in a timed event is often the difference between a gold medal and 4th place and no medal.

            The table provides absolute time improvements from the formula used by the authors.

Estimated improvementsi in 40km TT time (mm:ss)

40km time prior to training
Minimum
Maximum
Average
Novice
72:56
3:35
7:18
5:27
Well-Trained
58:35
1:10
2:20
1:45
Elite
52:02
0:32
1:33
1:02

Combining the chart detailing improvements from training and the other potential improvements described above into one table provides the table below.


Novice Cyclist
Well-Trained Cyclist
Elite Cyclist
Carbohydrate Beverage Ingestion
0:42 
0:36 
0: 32
Caffeine
1:24
1:03
0:55
Lighter Bike (flat TT)
0:13
0:07
0:05
Lighter Bike (uphill TT 3% grade, 20km)
1:34
0:42
0:29
Lighter Bike (uphill TT 6% grade, 20km)
3:38
1:52
1:15
Aerodynamic Positioning
2:00-2:30
2:00-2:30
2:00-2:30
Aerodynamic Frame
1:44
1:26
1:17
Training (minimum)
3:35
1:10
0:32
Training (maximum)
7:18
2:20
1:33
Training (average)
5:27
1:45
1:02

For the novice cyclist, the clear winner in providing the largest benefit is proper training in all scenarios except the uphill TT on a 6% grade (and just how often does someone compete in that event?).  And that is just using the minimum estimated gain from training.  If you look at the average impact, training more than doubles the benefits from every scenario except that 6%  uphill TT scenario.  As the cyclist progresses in fitness, other factors provide larger potential benefits although proper training still has a strong impact. 

Conclusion
            First, it needs to be noted that the information presented comes from mathematical models and needs to be taken in that context.  However, if one thinks about it, the general idea that training has the biggest impact makes sense.  Regardless of the kind of bike, position, nutrition, etc, a novice rider should have less of a chance of out riding a well-trained rider much less an elite racer.  
            The model ignores other factors that a coach brings to the table for the athlete such as skill development, pacing strategy, sport psychology skills and other factors the coach is able to develop in the athlete.  Leaving road time trialing for a moment and examining cross country mountain bike racing where aerodynamics are practically meaningless and the training issue and skill development becomes even a higher priority.
            Factoring in the skill, strategy and psychological benefits a coach can bring to the table and the case for hiring a coach to improve athlete performance is quite strong.  USA Cycling encourages its license riders to contact a USA Cycling licensed coach about becoming a client.  Information on coaching certification levels is available at www.usacycling.org. A listing of licensed coaches is also available at www.bicyclecoach.com (this can be linked from the USA Cycling website).
                                                 
i Jeukendrup, AE and Martin, J.  Improving Cycling Performance: How Should We Spend Our Time and Resources.  Sports Medicine, 31(7):  559-569, 2001.

What are the most important tools/gear I should carry with me while on the bike?


By PCG Coach Rick Shultz

Here’s the second most asked question … “What are the most important tools/gear I should carry with me while on the bike?”

This is a great question since it brings up a couple of ‘gotchas’ or catches to consider. So, let’s get to the list

MOST IMPORTANT ITEM(s) is your cell phone, house and/or car keys and driver’s license. I consider this an item since you can carry all of this in a small plastic bag and stuffed in one of your jersey pockets. Also consider carrying your insurance card, some cash and optionally a credit card.

When out on the road, or on your MTB, the #1 problem cyclists experience is a flat. So, this next grouping are essentials needed to get you back onto the bike quickly. Depending on what types of roads or trails you ride, many cyclists opt for a tire sealant. If you run clinchers, you can add a sealant to both tubes, if you run tubeless, add some to the inside of the tire. Sealant used in tubeless tires should last several months before drying out and needing to be added again. One area of concern for the tubeless route is how corrosive is the sealant to the inside of the rim. Do a little research and contact the wheel manufacturer first before selecting a sealant for your tires. I have seen a certain sealant used with a certain wheel and after 6 months, the inside of the tubeless wheel was completely rusted.

1)      SPARE TUBE – Carry at least 1 spare tube, AND, make sure that the
a.       Valve is the right type for your wheels. A Schrader valve won’t fit in a wheel designed for a Presta valve.
b.       Valve stem length works with the wheels you are riding. Tubes come with valves of varying length.
32mm
33mm
34mm
36mm
37mm
40mm
42mm
48mm
51mm
52mm
60mm
80mm
Last Sunday, I was on the ‘A’ group ride when one of the guys got a flat. We stopped and he pulled his spare tube from his saddle bag. The valve stem length was 48mm, he had 50mm deep rims. He just upgraded his 24mm wheels for 50mm wheels and forgot to get the right tubes. Luckily someone had a spare and we were back on the road. So, go out right now and check two things, (1) that your tubes will fit your wheels and (2) that your tubes are in good shape. Sometimes, when they sit in a saddle bag for a long time, they rub against other items in the bag and end up with a small hole. At the same time, check your CO2 cartridges to make sure they are in good shape, no rust or dents or other compromises.
c.       The tube is the same size as the wheels you are riding. It’s not a good experience when you pull out a 650C spare tube when you are riding 700C wheels.
d.       The tube material. Tubes come in;
                                                   i.      lightweight (butyl) – more for racing bikes, and where weight and durability is a consideration
                                                 ii.      standard (butyl) – these work best for all around general riding, club riding, club racing
                                               iii.      puncture resistant (sometimes called thorn-proof) – HEAVY tubes when you don’t want a flat
                                               iv.      self-healing (sealant already included) – HEAVY since they already have sealant installed
                                                 v.      lightweight (latex) – the LIGHTEST tube for racing only (since they are more fragile
Make sure to choose a material that will match your application. In general, standard butyl works best For racing on a smooth surface, use a lightweight latex tube. If you do get a flat, roll the tube up and patch it at home. For the cost conscious, when tubes have 3 patches and you get the 4th flat, time to throw it out.
e.       The tube’s wall thickness. These are most available size options. Most general-purpose tubes you will find are 0.8mm/0.9mm.
Racing
All-Purpose
Thorn-Proof
0.6mm
0.8mm
0.9mm
1.6mm
f.        The tube is the right diameter for your wheel/tire configuration. For example, an online bike shop has the following road tube sizes available;
18-23mm
18-25mm
19-24mm
19-25mm
19-26mm
23-26mm
25-28mm
28-32mm
35-43mm
Match the tube size to your tire size. For example, if you are running 700x25C tires, you can use 18-25mm, 19-25mm, 19-26mm, 23-26mm or 25-28mm tubes.
2)      PUMP/CO2 INFLATOR – This is for those that don’t want to carry a small/mini hand pump on their bike. Even though I have seen a lot of cyclists carry their hand pump in their jersey pocket, I have also seen 2 separate crashes where the cyclist had broken ribs due to the mini pump being in their back pocket. So, for safety’
A CO2 inflator system can be purchased as a kit that is comprised of the pump head, and 1 or 2 CO2 cartridges. With this system, there’s no need to carry a patch repair kit. Make sure you read the instructions since there are both threaded and non-threaded CO2 cartridges and you will need to us the correct one with the pump head. CO2 cartridges also come in different capacities, usually 12gm, 16gm and 25gm. The smaller capacity cartridges are usually used for road bikes while the 25gm is used for MTBs. There are lots of options out there so pick one that best meets your needs.

3)      TIRE LEVERS – you will need at least two to get most tires off. Tire levers come in 3 flavors, a) plastic, b) plastic with a steel core, c) heavy duty steel. Here are my observations having used virtually every type of tire lever made.
a.       Plastic – Most break easily, especially when trying to take off or put on a tight tire.
b.       Plastic w/Steel Core – Will also break easily where the steel ends.
c.       Steel Levers – DO NOT USE on modern road wheels, especially carbon wheels. Use only for kid’s bikes or big box store bikes.
MY CHOICE – The BEST tire lever I have ever used is Pedro’s Tire Levers, and, for the past 6 years, these are the only levers I have used. Even though they are plastic, I have yet to break even one! They currently come in yellow, pink, green and red AND come with a LIFETIME warranty – so, take your pick!
PRO TIP: ALWAYS wear eye protection when taking off/putting on a tire in case the lever breaks. You don’t want the broken plastic to hit you in the eye.
4)      TIRE BOOT (plus 4mm & 5mm allen wrenches) – What happens when you run over a piece of glass or metal and get a slice in your tire? You basically have 2 options, you can use your cell phone and call for help or you can boot the tire. The best boot material I have found is plain DUCT TAPE. I take both a 4mm and 5mm allen wrench(s) and lay them back to back so that on one end I have the angle of the 4mm and, on the other end the angle of the 5mm. That way I can use either tool if needed. I then secure them together using DUCT TAPE. I wrap the wrenches together with at least 10 turns of DUCT TAPE. This gives me plenty to use if needed. When I need to boot a tire, I can rip off the exact amount of tape to form 2-3 layers on the inside of the tire.
5)      MULTI-TOOL w/CHAIN TOOL – Pedro’s also has a $25 tool that does it all, including a chain tool. No more fixing a chain by pounding links in with a rock! Try the RxM Multitool instead. Again, a lifetime warranty.

PRO TIP – The valve stem hole (on the inside of the rim) on some wheels can be sharp enough to cut a tube. Take some sand paper or a small file and remove any burrs on the inside of the rim. This will ensure that your tubes won’t be cut where they insert into the valve stem hole.

Where to carry all of this? The right saddle bag will work the best for you. I prefer TOPEAK bags as they have always been consistently the highest quality – lasting the longest. The have a full range of bags including my favorite, the AERO WEDGE PACK. Sizes available are XS, S, M and L.

I know that there was quite a bit of information to go through. Spend some time and make a list of what you need. All of this can be procured at your LBS or on-line.