From All Posts

Screen Shot 2015-11-06 at 12.38.34

Mountain Bike Specific training: Part 3 – More data to validate Chronic Intensity Load.

So Jason Hilimire discovered my little blog on CIL and shared it with a good handful of coaches that liked what they saw. I’m really glad of that. My coach Dave Schell and I are really trying hard to make smart training easier, and it’s good that there are other people that have a need for that.

I plugged in some more data into WKO4 to see whether CIL was an accurate measure of Chronic Intensity for other athletes. These screen caps below are from Bryan Alders’ data, shared with his permission (Bryan is also coached by Dave Schell).


Screen Shot 2015-11-06 at 12.38.34

Bryan broke his collarbone in late March 2013. You can see this as both CTL and CIL plummet, nullifying all the base miles he worked hard for early season. Starting in May, he started riding and racing again. He had great race results and a perceived high level of fitness, even though his CTL never bounced back. His CIL though reflected that intense fitness that he’d gained through intervals workouts, short track races, and intense (<2hr) MTB races.

Bryan’s 2013 cyclocross season was also awesome, culminating in 12th place at US Nationals. His CTL remained completely flat – if he tried to use that as a metric of training progress, he would be demoralised and discouraged. CIL on the other hand reflects the accumulation of intensity throughout the cross season, and explains his results very nicely. If you look at his peak 1 minute powers (orange dots), they also correlate with CIL.


Screen Shot 2015-11-06 at 12.38.13
Bryan raced mainly 50 mile MTB races and 2 hour XC races in 2014. His CTL and CIL agree with each other for most of the season, with CIL increasing more quickly as soon as he started racing midweek short tracks in Boulder (late May). Bryan raced a moderate cross season, with little training in between, and that’s shown by a maintenance of CIL and a flat CTL. It’s likely that longer (>2.5 hour) MTB races are the point at which CTL and CIL overlap – they both do a good job of mapping fitness.


Screen Shot 2015-11-06 at 12.35.48

Staying on the theme of narrating Bryan’s life through data, 2015 represents what happens when you get married – Bryan trained hard in the spring, gaining CTL and CIL equally. During the summer, he stopped training as hard as preparations for his wedding ramped up. But he still raced well – he won some 2 hour XC races in July/August, at the point where is CTL is already dropping. Looking at CIL, his Intensity Load is again more apparent. Bryan is now in the midst of a successful cross season. The CIL line has ramped up quickly from mid week interval workouts and weekend racing. CTL would not reflect this – Bryan’s riding time each week is around ~7 hours, which is not enough for CTL to credit him the work he is doing.


Mountain Bike Specific Training: Part 2 – Measuring bumpiness


Mountain Biking is really bumpy. And most riders think the bumpier the gets, the better. I agree. I like my races technical. This creates a problem for those that train with power. Putting down power over bumpy terrain is a different beast than doing so on a smooth road or trainer. Rather than just needing well tuned prime movers to get the power down, you need accessory muscle activation to stabilise yourself.

Measuring this instability, and then recreating it in training has thus far been impossible. Most mountain bikers ride off-road as much as possible, but when that’s not an option, we have to resort to road riding. If we could correct power data to account for the terrain over which it was produced, we’d have a much better idea of how hard a race or training effort was.

Dave Schell and I have begun trying to measure this instability. We’re currently using the Wahoo TickrX, a heart rate monitor that also measures trunk angle and upper body movement using accelerometers. It’s designed for runners, but we’re trying to hack it to be useful for mountain biking.

Here’s the theory: when riding along a smooth road, your upper body is almost completely still. The bumpier it gets, the more your upper body will move. Using this, we begin to estimate the bumpiness of a ride, and use that number to correct power data accordingly.

ΔTrunk Angle

IF [(trunk angle) at t(n)] ≠ [(trunk angle) at t(n+1)] THEN count = 1)/total time in seconds

This gives us a number between 0 and 1 that we can use to score the “roughness” of the ride. For example, a score of 0.6 could be translated to a ride that was 60% rough and 40% smooth.

It’s reasonably crude, but it works for creating a ride ranking that can easily compare rides. The things it’s missing: it does not factor in magnitude of change in torso angle. Bigger bumps, drops and step ups should be weighted more heavily. It doesn’t factor in stopped time, when torso angle will likely be 90 degrees to the ground and thus be a big change from riding position. Or reaching for water bottles and shoes adjustments etc. I’m thinking that these actions will be few enough over the course of a typical ride that they should muddy the data too much.

To account for magnitude of change, I subtracted one time point from the next to give an actual degree of change. This was the second attempt:

When Wtn ≠ 0, ΔTA/time = [(trunk angle)tn-1 – (trunk angle)tn]^2) / (total time in seconds)

ΔTA: Change in trunk Angle

Wt: power in watts at time t

This then gives us an average degree of change of trunk angle. This metric is unbounded, unlike the number above, so it’s a little harder to use, but still gives a good comparision. It has to be squared to account for the negative changes in torso angle. In theory, matching the torso angle data to power meter data should allow us to use only data points where power is not zero. Then we could see the changes in torso angle while pedaling, which is what we’re really getting at: how interrupted was your power output?

Correcting the raw power numbers would be pretty simple. If we assume that a road ride would end up giving a Bump Factor of 0, power could be multiplied by ((BF/100)+1) to give terrain normalised power (TNP)

TNP = Power * (BF/100+1)

for example:

300 watts on a smooth flat road, where the bump factor = 0

TNP = 300 * ((0/100) + 1)
TNP = 300 w

300 watts on a mountain bike trail where bump factor = 4

TNP = 300 * ((4/100)+1)
TNP = 312 w

Thus, the terrain could be said to cost an extra 12 watts. A first trial run of riding Heil Ranch outside of Boulder gave a BF of 4, so that’s a good figure to start with This is likely an underestimate. Once the final metric has been calculated, we can begin working out what the actual correction needs to be.
This is a work in progress… there’s a lot more data that the TickrX can capture, and we’re hoping that some of the metrics it’s already recording could be hacked into a riding version. My coach Dave Schell is working with the people at Wahoo (who make the TickrX) to figure out how we can get raw data from their accelerometers to determine what movements are actually made during MTBing, and which ones are important. Like I said, this is a VERY EARLY work in progress….

Screen Shot 2015-11-01 at 15.18.19

Mountain Bike Specific Training: Part 1 – Chronic Intensity Load

I’ve been using this off season to think about training smarter. With my coach Dave Schell, I’ve been working on optimising the tools we’re using to measure my training. Most of the online tools we’re currently using have been developed with road cyclists and triathletes in mind. The problem is this: the tools are skewed by using aerobic and continuous exercises as their datasets. Mountain Biking is a discontinuous mix of anaerobic effort and recovery. The models have been developed around making training optimal for events like a 40 km time trial on the road. This doesn’t work for mountain biking.

Mountain Biking (and cyclocross, and crit racing for that matter…) is different. Duration is not the key to success. The appropriate volume of the correct intensity is the key to success.
But TrainingPeaks (and by proxy most coaches) use a metric called the Chronic Training Load to measure how much training an athlete has done, and how fit they have become as a result. Chronic Training Load is basically a weighted 42 day average of your training. It’s problem is that it weights the duration of exercise very heavily when figuring out how hard a ride is. That’s not appropriate for Mountain Bikers. Instead of using the Training Stress Score to build a model of Chronic Load, we are using the Intensity Factor that is built into TrainingPeaks.

Standard Chronic Training Load:

CTL= [Todays TSS * (1-e^(-1/42)] + {Yesterdays CTL * (e^(-1/42)]

We replaced the TSS score (the main weight of duration) with Intensity Factor:

Chronic Intensity Factor: 
CIL = [(100 * Todays IF) * (1-e^(-1/42)] + {Yesterdays CIL * (e^(-1/42)]


TSS = [(s x NP x IF) / (FTP x 3,600)] x 100

s = Time in seconds

NP = Normalized Power

FTP = Functional Threshold Power



This is a quick screen capture from the performance management chart in WKO4. The traditional CTL measure is displayed with light blue bars. As is normal, CTL builds from the beginning of the year as your accumulated training load builds through the base miles.
CIL is described by the dark blue line. It also builds through the early season as intense training accumulates.
What is really noticeable is when CTL and CIL deviate. Starting in late May (my peak race season), CTL suggests that my training load is decreasing as my duration decreases in response to more racing. CIL continues to increase and remains high through July, which more accurately reflects the intensity of the training and racing.
For the MTB racer and potentially crit rider, using CIL in conjunction with CTL would be very valuable. In the early season, it is very useful to ensure that the base miles a rider is completing contains enough quality – if CTL increases much faster than CIL that might be a problem. During race season, the steady decline of CTL can be a worry for coach and athlete – is fitness really decreasing? Using CIL here would show that the quality is either remaining or increasing even as CTL decreases.



Four Passes Loop: Day Three


Cold. Much colder than the night before. The clear skies that put us to bed let the warmth flow upwards, and we woke to frost covered bushes. Much more tea and porridge were needed to get the boots laced. But the packs felt lighter when we pulled them on, and that ache was now familiar and reassuring. Even after two days, the routine was simpler and more straight forward. Christa set off at an astounding pace – marching quickly onto the lower slopes of Buckskin Pass.


We’d seen glimpses of it the day before, but as we were climbing it, we couldn’t see anything but the next 100 feet of trail. We broke through the trees surprisingly quickly and found we’d gained 1,400 feet of height really quickly. Only another thousand to the summit.

We slowed and sucked in the scenery, looking back to where we’d been before; trail riders pass, the peaks of Hagerman and Snowmass now clear in orientation. It’s amazing what a change of perspective can do for you. The going was smooth, and we found our way into the tundra quickly, the final switchback giving us the view we’d been dying for: the north face of Maroon Peak. It didn’t disapoint. Its huge face once again plastered with another layer of snow.

We sat for as long as we could, but the wind whipped us back onto the trail, and the thought of finishing pushed us downwards. As we descended the temperature soared and we took layers off much faster than we put them on at the top. Lunch – the freedom to eat as much as we could manage. With only a couple miles left we sifted through the remains of our food, encouraging each other to eat just one last bite of something rather than stuff it back into our packs. Christa’s knees were aching, so we unloaded her pack as much as we could then set off downwards again, marvelling at how far up we really were.

DSC04611 DSC04619 DSC04616

Finally the trail popped us onto where we’d been two days earlier, at Crater Lake. People were everywhere – now within that radius where people walk from their cars. The final section of trail back to the car was much steeper than we’d thought. Looking back at the first mile of our trip, we were all motivated and fresh, and didn’t realise that what we climbed was as difficult as it was.


We stopped on the shores of Maroon Lake and marvelled at the mountains and our accomplishments, but also the number of people around us. I sat and felt smug that I could get out into the real mountains, away from the car and the crutches of convenience. But moreover I felt gratitude that my parents could come along and do it with me. They are adventurous beyond most people’s comprehension, but they also have the ability to follow through on that ambition. It was a tough hike for anyone, but the satisfaction made it really worthwhile.



The Four Passes Loop: Day Two


Dawn broke with warmth and clearer skies. Down jackets and porridge. Enough tea to clear the vision and lace the boots. Camp was broken and bags repacked. Achy hips resumed the weight of the packs and strained at the first, hardest, step.


But the trail flowed out and down the valley. The trail bisected the Crystal River at a low and wide crossing. Freshly laced boots were removed and the ice shot through our feet as we tested the balance of our laden bodies. Sitting and retying our boots as the sun moved from behind Maroon Peak to our east: layers readjusted. Jackets off, shorts on. Sun cream applied.


The trail forked and we went left. Trail Rider Pass, number three on the list, nothing more than a line in our mind, hidden above us by the first ridge. The map showed tightly stacked contours and our legs agreed. Pushing skywards in short vertical steps. We broke over the top of the ridge at 11,800 feet after a solid hour of uphill.

DSC04510 DSC04514

The wind whipped us just slightly, and the trail sank down into the high alpine basin. Another small lake with the water curling over the surface as the breeze pushed it along. We looked east at the Maroon Bells. Another coating of snow on the north faces had been applied last night. The red of their rocky faces now alternating with bright white lines. We stopped in the shelter of some rocks and looked up at Trail Riders Pass. Unlike yesterday, we didn’t see anyone on the top. We’d encountered a spread-out group of hikers earlier in the day, but approaching the slopes of this pass made me feel like we were finally escaping the grasp of easy access. There weren’t switchbacks. The trail cut straight up the southern slope of the pass, giving us a great view of Hagerman Peak and Snowmass Peak, both 13ers, to our west. We knew that Snowmass Mountain, a 14,000 footer was hiding somewhere close by, but we couldn’t get see its summit. I knew it was going to be windy on top. On the way up, little cuts in the rock had shot fierce winds at us. We peaked our heads over the top to feel the full force of the wind coming in from the north. Cold Alpine Autumn wind.


From the top of Trail Rider pass, Snowmass Lake was sitting comfortably in the basin below. 2000 feet below to be precise. The maroon slopes around its shores were plastered with bright yellow aspens that contrasted against it blue waters. Primary colours in the mountains. The way down was, once again, longer than anticipated. Without the drive to reach the top, the downhills splay out in front of you. The huge packs on our backs pushed us into the ground, testing our knees at each step. From tundra to trails flanked with huckleberrys, to scrub willow, and finally back into the trees. We kept descending. Past a huge scree field and eventually we picked our way through the deadfall to find the shore.

Frigid, icy, gently lapping. It needed to be jumped in, and we obliged with a quick splash. It ended up being a very quick splash, followed by a solar-powered dry on the rocks, and then we saddled up again for the last push towards our second campsite of the trip. It was tempting to stop at the shores of Snowmass Lake and camp there, but with plenty of daylight and a little energy left, we trucked onwards. Around the corner and up valley, directly towards the feet of Maroon Peak. Buckskin Pass was the final hurdle, and we wanted to tackle it as early as possible in the morning.


We crossed Snowmass creek on a sturdy wooden bridge, then coasted along next to a beaver-damed creek. As the valley narrowed, we found a campsite perched on a rocky outcrop overlooking the marshy lake and the peaks in the distance. Fire > Food> Tea, a few card games and then we watched as the sun threw its final rays over the mountains. The trout jumped in synchrony in the lake, chasing every bug that got too close.

The Elk picked up their tuned from where they left off last night, and we eventually settled again into our sleeping bags. The clear night lead to a quick temperature drop, and we slept fully clothed.


The Four Passes Loop: Day One


There are plenty of warnings about strenuous exercise at altitude. Most of them caution that coming from sea level is a bad idea. To give yourself more time. To relax and enjoy the view. But what’s the fun in that? My parents arrive in Colorado on a regular basis – almost once a year. But that’s rare in the grand scheme of things, and leaves too little time to waste with aclimitisation and relaxation. We had things to do. Passes to hike.


The Four Passes Loop is a 28 mile circular hike around the Maroon Bells in Central Colorado. The Maroon Bells are some majestic 14,000 foot peaks of ruby coloured granite. Part of the Elk Range, south of Aspen and north of Crested Butte. Remote. Wilderness with that big W: nothing but feet and hooves allowed to traverse their hallowed slopes. The four passes crest the flanks of these huge mountains, giving us a three-day, 360 degree panorama of the peaks. In Colorado, roads will only take you so far, and a days hiking not much further. To really explore this state, sleeping bags and camp stoves and huge heavy rucksacks were needed. Christa and I loaded my parents down with as much as they could carry, and drove them to the picturesque Maroon Lake.

We set off south under greying skies with the aim of hiking the loop in three days. The guide books say it takes four days. I know people who can run it in eight hours or less. I thought three days was reasonable. With the intention of covering 14 miles and two mountain passes, we strolled gently up the trail, away from civilisation. The newly loaded packs weighed us down, and my parents pace fell off our early enthusiasm. We passed Crater Lake. Still smiling, quickly acclimatising to the rate at which calories will be burnt.

A stop for lunch at treeline below West Maroon Pass. We assessed the situation. Dad folded to the ground and devoured a sandwich in near silence. Mum stopped talking for more than a minute. They were tired. We rijigged our loads and saddled up again, inching our way towards summit number one, and crested it by noon. Five hours of hiking and only three passes left to go.


The going got easier. My parents found their stride: the altitude tempering their enthusiasm and them coming to terms with the needed moderation in the pace. We made slower progress, but less puffing, less worry that the thin air would fail to support the huge packs on our back. We stopped at a small lake below Frigid Air Pass and looked up at the final push. Reclining on our packs, the alpine wind just preventing that easy trailside snooze. Then we started up the slopes when we were ready, a better understanding already about what this trip would take to get to the end.DSC04470

We crested without problem and admired the views south towards Mount Crested Butte, and west to Maroon Peak, and all around at the expanse of the Elk Mountains for which we didn’t have the time to name. From the top of Frigid Air Pass, the campground was within reach. Downhill to finish line number one. A long way down. The valley, and Fravert Basin, stretched below us. We set off in search of King Falls. The destination for this evening. It was a long way down. An hour of downhill and we took a break. Sat on a downed tree and ate an apple. The rain sprinkled lightly and a little harder, and the mix of dried sweat and warmth started to dissipate in the colder evening air. We strolled along next to the Crystal River. The crackling and roaring as it approached the falls, and we plummeted with it as it dropped. We pitched ourselves at the bottom. The clear pools slowly exiting the falls and working their way down through the broad meadow below. The fire started slowly among the damp foliage. Fail attempts at fire and a slow burning stove tested our meagre energy reserves. But tea was brewed and food cooked.


Fire warmed us until the sleeping bags called us into their anticipated warmth. Sleep came quickly. Broken, fitful camp sleep. Elk herds bugled in lengthy conversations in the trees above us. Camp sleep – not the quality you’re used to, but filled with quality of its own.


The Vail Outlier Festival // Scott Spark XC race


Who puts a mountain bike race on in September? That’s just not the way Colorado works. That’s cyclocross season. Everyone knows that. But what happens when you go against the grain, you line up in the hills against the glorious burning backdrop of the turning Aspen trees, and race your friends to the treeline and beyond, then descend through orange hued groves of trees back to town? That would be the Vail Outlier.

If you’d been paying attention in Colorado, you’d have seen a trend arriving. The wet, heavy and underrated spring has been wreaking havoc on the enthusiasm of Mountain Bikers for plenty of years. The incessant hype has pushed races earlier and earlier, until every year is broken with cancelled races, low turnouts, and snowy drives past pristine ski areas on the way to a bike race. The Rumble at 18 Road in Fruita is a prime example: an early April date on fantastic desert trails is so enticing, but the reality of a snowy six hour drive, and heavy clay trails when you arrive has stopped people arriving. Even on the Front Range: the early May “Battle the Bear” cancelled due to the needed and awesome and wholly good spring rain. The Firebird – the earliest anyone dares venture into the Aspens, is just too early to be reliable year in, year out. In a state where the snow drives life – the economy, the environment, and everything in between – it seems perverse for mountain bikers to be praying for dry springs so we can ride our bikes.


And then you focus on the alternative. September. It’s been happening for longer than I’ve been here. Jeff Westcott organising the Fall Classic in Breckenridge is a prime example. The high country is sparkling with glorious colour. The nights have drawn closer and the temperature has plummeted, and the trails are tacky, winding empty ribbons. A highway through beautiful Colorado. It’s perfect. The Vail Outlier needed to happen. But with the Front Range on Cyclocross duty, who would turn up? The waning motivation of the masses is a tide to be fought, to be rowed against. But we did turn up. The normal crew and others. Fitness unknown, to be tested again just as it would with early spring.

A casual line up followed by an iron-tasting sprint from Lions head village in Vail. The leaders were gone. So close, but gone. I could see them shifting, drinking, taking turns on the front of their majestic lead group, but I was afloat behind. With Jay Henry to pull me up the hill, I held on to the top, battling against my bike and my screaming lungs, and then sailing peacefully across the top of Vail Mountain. No one in sight: the leaders far gone, Jay still riding scared ahead, unknown to him that my fight to catch him was being tempered by the huge views of the Sawatch and the Holy Cross Wilderness to the south. Should I be allowed to have this much fun when I race? A few final kickers and then the release of the descent to Vail. Endless. Finger aching and endless. I hit it hard and find the groove of the season-weathered berms as I descended down the mountain. The occasional look up the hill; no one through the trees. I cruised across the line in exhausted satisfaction. In sixth. No fight for the win, but no need for it either after that ride.


This is my plea to you: Don’t race in March. Ski. Or go south – find the Desert, and leave Colorado to its snow. Come back in May, or better yet June. Just as the Aspens get to their darkest green. And then hang around a while. Stay till it gets really good. Till September happens. That’s bike-racing season.


Riding from Boulder to Winter Park

The ride up and over Rollins Pass is a classic. A proper Colorado high country adventure that takes in the very best of riding in both Boulder county and its western neighbour – Grand Country.

After a rainy ride over on day one with the Thorpe Crew, plus Zach White, Eric Porter and Kelly Emmitt, I made a hasty return back over the pass the next day. The weather was hugely improved, and I stopped plenty to take a look around. I also took the opportunity to take the fun way home, and managed to ride trails almost all the way back to Boulder. This living in Boulder County thing is pretty darn awesome!


The Steamboat Stinger 2015 – the best trails ever?

Round five of my unbroken streak of attending the Stinger. I’m still a bit surprised that I’ve managed to attend every year this race has been going. Between moving across the atlantic a few times and plenty of other life changes, it’s rather funny that the Stinger has become such an unmoving fixture.


I don’t normally include the geeky details in blog posts, but I will for a change: I ate 1160 calories (five packets of Honey Stinger chews, two gels and one waffle), drank 220 calories (two tall bottles of Kiwi/Lime flavoured Carborocket), and also drank six bottles of water, for a total of about three litres of fluid. TrainingPeaks estimated I spent 3300 calories during the race, so I finished with roughly a 2000 calorie deficit. No cramping this time, even though it was really hot out there.

I came third this year, like last year, and the year before. But I’m in no way disappointed with that. In fact, I’m really happy with my race. The field every year is “national standard” strong. This year, Kerry and Jamey from the Raleigh Clement team lined up for the first time, and Russell Finsterwald came back to see if he could add to his two previous wins. We got to the line in time to talk to the other 115 men in the Open field. It’s a big race, with 600 starters total. The start is one of the most brutal in all of marathon racing; straight up the ski slope at Howelsen Hill. I was gapped from the gun, with Russell setting a fierce pace. I settled into about fourth, and ground my way towards Emerald Mountain.

From town, Emerald Mountain is the north facing hill with the radio towers on top. It looks small compared to the main ski area. But it’s not. Its concave face ramps up steadily, and “the stairway to heaven” trail takes you on the most direct route to the ridge road on the summit. Cleaning this section is more a point of pride than race tactics. It hurts, and you’re on the front of your saddle hoping for traction. From there, there pleasure of the Ridge Trail comes into view. The aid station buzzes by in a blur, and you’re descending for a solid 20 minutes. It’s bliss. I got caught by Kelly Magelky, Kerry Werner and Jakub Valigura on the short dirt road section before the second climb, and I happily sat with them all the way to the top. Kelly set a great pace and I was content to just sit on.

We split apart a little on the descent – Kerry lead the way and I followed closely, but decided to stop to take a tactical bathroom break on the way down. I chose the spot where I’d loose the least momentum, but it did cost me the chance to follow Kerry on lap two. Coming through the start/finish is tough, knowing you’ve got to go do it again. At this point I was still in fourth, with 5th – 8th close behind. It’s daunting knowing that everyone is chasing you. With riders so close behind me, I set a pretty hard pace, aiming to stop any freeloaders getting onto my wheel without working for it. By the time I hit stairway to heaven for the second time, I was alone and feeling pretty good. I cruised down the ridge trail for a second time, and then began climbing the Bell trail. It’s a long winding climb. Even after five times racing (so 10 times up this trail), I forget the in’s and out’s of the climb. By the time I got to the unofficial aid station near the top, I suddenly started seeing glimpses of a blue helmet ahead of me. A Raleigh Clement helmet. I thought it was Kerry, but it was actually Jamey Driscoll. I came over the top of the climb with him in my sights, and soon reeled him in. I didn’t quite know how blown he was, so I rode the last descent as hard as I could. I crossed the line in 4:15, pretty much the same as every other time I’ve raced. I was 10 minutes down on Russell, which wasn’t too bad, and four minutes back on Kerry.


I was really happy to make the podium after a rough first lap. It took quite a lot of suffering to pull it together on the second lap. Since racing in Wisconsin at the end of July I’ve had some down time; not riding much and trying to let my body catch up with the endless fatigue. Without any long rides of any kind, I didn’t know how I’d do, but I think the time I’ve spent off my bike has actually been really valuable. I’m motivated again to be racing, and I’m planning a late season campaign of Colorado’s best races.