Lactate Thresholds

In my first blog entry I said I'd talk about training for the Leadville 100 MTB race. So far I haven't done much of that, in part because we haven't really started our focused training for the 2009 race yet.

So this is the first "real" training entry, but it won't be the last.

After our unsuccessful attempt to ride Leadville in 2004 Phil and I took a few days to lick our wounds, then we sat down and came up with a plan which we hoped would allow us to succeed in our next attempt.

The first step of that plan was to have lactate threshold testing performed at the Boulder Center for Sports Medicine. We hoped the information we learned could then be used by a coach to help develop a training plan tailored to our fitness levels.

Lactate threshold is one of the most common performance markers used by many athletes and coaches. The point is to learn the highest intensity at which you race and train before hitting the wall from high levels of lactate and metabolic waste in your bloodstream.

What is Lactate Threshold?
The energy required to move is supplied from the breakdown of adenosine triphosphate (ATP). The body can store about 85 grams of ATP and would use it up very quickly if we did not have a few ways of resynthesizing it.

There are three energy systems that produce energy: ATP-PC (short, explosive movements), glycolytic (intermittent hard intervals) and aerobic (endurance exercise).

Athletes most commonly attribute the intense burning and pain felt during exhaustive bouts of exercise to lactate, which is produced by all energy systems, but becomes an issue when it accumulates and can't be processed fast enough. When you demand energy faster than your aerobic energy system can produce it, your glycolytic energy system picks up the slack. Even though glycolytic (anaerobic) literally means without oxygen, it’s not that there’s no oxygen available, but rather that your aerobic system is going as fast as it can and you still need more energy. The glycolytic system is fast because it doesn’t use oxygen to burn carbohydrate, but it’s less efficient and produces less energy, per unit of fuel burned, than the aerobic system. Your body has to clear lactate from working muscles and process it back to useable fuels, and lactate threshold is the point at which production outstrips the clearing process and lactate starts to accumulate in the muscles.

Why Lactate Threshold Matters
Your lactate threshold essentially defines the upper limit of your sustainable efforts in training and competition. Once you cross over and rely more heavily on your glycolytic system for energy, you’re exercising on borrowed time. The accumulation of lactate will hinder your muscles’ ability to contract, and you will be forced to slow down or stop.

The more work you can do before reaching lactate threshold, the better. If the pace you can hold at your lactate threshold is higher than the pace your competitor can hold at his or her lactate threshold, you go faster, reach the finish first, and win. Being able to do more work at lactate threshold also means maintaining a lighter pace is even easier. While your main rivals are burning energy fast, riding at their limits, you can stay right with them and rely primarily on your aerobic system. This saves valuable energy for hard efforts later.

An athlete’s initial lactate test provides an indicator of fitness level and a starting point for training. Depending on the protocol used, the following data can be acquired through a lactate test: maximum sustainable power (cycling), recovery heart rate (how quickly the athlete’s heart is able to return to recovered levels), speed and power at lactate threshold, and a relative index of fitness (i.e., speed or power divided by the athlete’s body weight).

The real power of lactate threshold testing comes from comparing test results over time. Provided you’re training and striving to improve, regular lactate testing provides you with concrete evidence of improvement, or lack thereof, throughout the season. A history of lactate tests should show changes in fitness, characterized by: increased power and/or speed at threshold, improved recovery heart rate, a higher lactate threshold heart rate, and a higher speed- or power-to-weight ratio.

Consistency is the key to improving performance at lactate threshold. You have to accumulate a lot of work at a steady workload to place the appropriate amount of stress or load on the system. Since you can’t spend a lot of time working above threshold, these training intervals have to be at an intensity just below your threshold.

In subsequent posts I'll talk more about how to use your lactate threshold (LT) when developing your training plan.

I am being re-tested at the Boulder Center for Sports Medicine on October 2, so I'll also provide details of my test and how I will use that information to structure my training plan for the 2009 season.

Track Cycling

One of the great things about living in the Denver area is the abundance of recreational opportunities - both as spectators and as participants. While I'd usually opt to go for a ride on a gorgeous autumn Saturday, I talked Phil and Jeffrey into going down to Colorado Springs to watch some of the 2008 USA Cycling Collegiate Track National Championships.

Even though I've been an avid recreational cyclist since the mid-80s, I've never paid attention to track cycling, and don't know much about it. We watched the men's team pursuit and the women's match sprints.
The match sprints seemed to have a lot of tactics involved, while the team pursuit involved 4 guys on each team just going all out until someone blew up and fell off the back - then the remaining three tried to stay together until the end.

We rounded out the day by stopping to watch some of the Pikes Peak SuperCross event at Bear Creek Park in Colorado Springs. It was fun to watch the mounts, dismounts and near-misses. Maybe we can do that after all . . .

Jean – Leadville Crew Chief (2004, 2005, 2007 . . . & 2009?)

In the summary of our 2004 race I mentioned our valuable crew chief, Jean. Jean's birthday is tomorrow (September 12) so it seems like a perfect opportunity for a shout out.

We met Jean at our gym (Athletic Club at Denver Place, now "Forza") several years ago. Jean was a regular at the two-hour Saturday morning Spin class/sweat extravaganza which we used to attend during the dreary winter months. When she first heard of our plans to ride the Leadville 100 she volunteered to crew for us.

Neither Phil nor I really understood: 1) why anyone would be silly enough to volunteer to wait around all day long just to support us; or 2) why we needed support (remember – we still hadn't figured out it was a race).

As the time for the race drew closer, we still didn't realize how important it was to have a personal support crew. But Jean was insistent that she'd be there for us, so we shrugged our shoulders and thought – "That's really nice. Odd, maybe, but really nice."

Friday before the race, as we spent hours fussing with our gear – "Do I really need shoe covers? A raincoat? Will a vest be enough? Rain pants? How much food should I carry? How much should I leave in the drop bag for Jean to carry to the feed zone? Sunscreen? Advil? Pepto Bismal? Electrolyte tablets? Chamois butter? Aaargh!!!" – we began to understand how crucial it was going to be to have a sane person out on the course who could talk us off the ledge as needed.

We made a lot of extra work for Jean that year just because we didn't know what we were doing, so it was difficult to give her any meaningful guidance. But Jean took everything in stride – including the fact that we put her up in the skankiest hotel you could imagine. [Any Trail Lodge in Leadville – to be avoided at all costs. Sleep in your car if you must, but don't sleep there.]
Saturday morning at 5 am Jean was up and ready to help any way she could. She held bikes and jackets, gave reassuring hugs, back pats and pep talks until – BOOM. We were off. And Jean's really long day truly got underway.

She had to fight the traffic out to Twin Lakes. Find a parking spot. Find a "camping spot" to wait for us. Haul the Rubbermaid tubs we had loaded up with the gear we might – or might not – need at least 1/2 a mile or more to the pit area. Our friend Chris's wife, Patty, was also setting up a pit area, so she and Jean were able to find a space and get hunkered down for the wait.

By the time I rode into Twin Lakes (outbound) I can't even tell you how great it was to see a familiar, friendly, supportive face. And when I came slinking back into Twin Lakes (inbound) with a pounding migraine after the Columbine Mine climb, it was so hard to tell Jean I was quitting. I didn't want to let her down. She had sacrificed her weekend and was so supportive, saying "You can make it, c'mon, keep on going . . . ." But I couldn't make it, and I couldn't keep going. So Jean loaded me up in the car and we headed over to the Pipeline aid station to cheer for Phil.

We watched some racers go through the aid station looking strong, while others pulled over to vomit or cry or stretch out cramping legs. And we waited. And waited. And paced. When Phil rolled up it was obvious he was DONE. But Jean gave him a drink and a pep talk and a pat on the back . . . and he just shook his head and said, "No I can't do it. I'm done."

So Jean loaded up his gear, too, and drove us back to town. It was a very quiet, dispirited drive. But by the time we got back to Leadville Jean was trying to cheer us up. We both felt too awful for it to have much impact, but that's just Jean – she is naturally encouraging and supportive of her friend's attempts to challenge themselves.

Several months later, when we told Jean that we were going to hire a coach and try Leadville again in 2005 the first thing she said was "I'll crew for you." Silly girl. But this time we knew both how much work it would be and what a gift Jean was offering. We jumped on the offer – and made sure to secure much nicer lodgings for her!
Happy Birthday!