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Determining Lactate Threshold?

Dear SkiPost,

You mentioned Max Heart Rate but also Lactate Threshold last week. What is it? How do you determine Lactate Threshold and can you improve it?

FB

 Lactate Threshold - (RPM's - how high can you race the engine?) Lactate threshold (LT) is the ability to continue using the aerobic system to replenish ATP (Immediate Energy) at high speeds. It is expressed as power output at LT, velocity of LT or percentage of Vo2 max. LT is one of the best predictors of endurance performance.

Lactate Threshold changes day-by-day and, with training, improves week-by-week and month-by-month. The only way to know, and "know" is a bad term to use because it is a changing value, is to take a lab test aimed at finding the threshold.

 Athletes have to learn to feel the threshold as they cannot get tested everyday. The test, as well as using a portable lactate tester in training, serves to reinforce or confirm what they feel their threshold is, or what they feel their easy pace is, etc.

 Recreational skiers can get tests at university laboratories or better sports centers for very reasonable prices.

If they aren't interested in this, they will have to use a formula and/or go by feel. It's a comfortably hard pace that can be maintained for upwards of an hour and a half. Formulas are not accurate but may give you a start. A skier's threshold is often between 80 and 90% of max (and even higher). Wear a monitor and, starting slowly, build up your pace gradually paying close attention to your breathing and heart rate. When your breathing is hard but rhythmic and in control and you feel taxed but as though you could go for a good long while then you are probably around threshold. When your breathing becomes a bit ragged and just out of control, and you feel that you could not go for very long then you have crossed over your threshold. Note your heart rate all along the way. The heart rate where you are running a bit ragged is above threshold, so error low. It can be the case that you have predicted your threshold at 175 one day but are running ragged at 173 another day.

What you hope is that you notice the running-ragged-heart rate creeping up. 

If it is going down, then you know you are training too hard, too much, and/or resting too little. It is a flexible value, so don't think that this can all be boiled down to some numbers. You will have to be involved in deciding for yourself how fast to train regardless what the hr monitor tells you.

 Don't make it too complex. Easy feels easy, hard feels hard... tired feels tired. Trust what you feel, and train well.

Andy at SkiPost

Determinants of Performance

1. Vo2 Max - maximum oxygen uptake (Engine Size - how big is the engine?) This is the ability of the circulatory system to transport oxygen and of the muscular system to extract and use oxygen. Vo2 max is an excellent indicator of aerobic fitness, but a poor predictor of performance within a homogenous group of athletes.

2. Lactate Threshold - (RPM's - how high can you race the engine?) Lactate threshold (LT) is the ability to continue using the aerobic system to replenish ATP at high speeds. It is expressed as power output at LT, velocity of LT or percentage of Vo2 max. LT is one of the best predictors of endurance performance.

3. Economy - (MPG - how many miles per gallon does your engine get?) Economy can be defined as the amount of oxygen that it takes for an individual athlete to go a given speed. More economical athletes will have a lower oxygen cost at a given pace relative to a less economical athlete. This can explain why an athlete with a lower VO2 max can still outperform an athlete with a higher VO2 max. Economy is one of the best predictors of endurance performance.

4. Strength. Strength is defined as the maximum force that can be produced in one all out effort. Muscular endurance is related to being able to maintain a submaximal force repeatedly.

Pelvic Muscles?

I have been training on my roller skis lately and struggling a bit with balance since roller skis have significantly less surface area on the ground. I am sore in places I cannot talk about in public. I have been reading that athletes of both genders sometimes have problems with pelvic floor muscles. I don't have any problems I can just feel them working. I am curious how pelvic floor muscles contribute to balance specifically in cross country skiing. Are they considered part of your "core" that we should be training for balance? Are there any warning signs athletes should be aware of that we are training too hard or too little? Are there any specific training exercises we should be doing to keep pelvic floor muscles healthy and improve balance?

Thanks,

MN roller skier 

Dear MN Rollerskier,

You are addressing something many of us have experienced in the early ski- or rollerski season, especially if we encounter conditions we are less accustomed to, such as balancing skis on ice or rolling on narrow wheels.  It is best to look at muscles in the core and pelvis as part of the "system" we use in any weight-bearing posture or motion, such as standing, walking or any movement on the legs in good body alignment, rather than something mutually exclusive to skiing.  As an active, fit person, you should have a good starting platform for training on rollerskis, and the general advice is to accept you are treading into new or seasonally unfamiliar territory.  Practice, recover and progress in your skills; you are most likely describing a common reaction rather a serious problem.  Here are some practical advice:

•        Maintain proper, erect, posture that will let you stay flexible and balanced in all three planes.  Rely on skeletal support and let the small muscles in the body regulate the balance.  The large muscles are only working intermittently for propulsion and should be mostly relaxed.
•        Assume the basic, or fundamental, athletic position; remember all ski motions are operating in, or passing through, this body position.  High hips, bent ankles and knees, neutral shoulders, etc., both buttocks and abdominals in, and so forth.
•        Maintain good, stable, weight distribution on the soles of the feet and both legs when standing neutral.  Employ full weigh shift when riding one ski, and weighing the ball of the foot when leaning forward and executing the kick-exchange or push. 
•        Although we lean forward in skiing, maintain good upper body posture rather that sinking in, avoid sitting in the rear or arching the back.
•        Wear appropriate boots and bindings for the technique, skis and surface you are venturing out on, and make sure your wheels are wearing evenly.  You need to be stable.
•        Start a comprehensive, full body strength program; you have already identified areas that could use additional work.  Keep in mind that strength is a significant factor in ski training; good skiers train comprehensive base strength, max-, explosive-, and ski-specific strength through the yearly training cycles. 
•        Practice on the equipment, including the items above, will increase familiarity with the new or untrained elements.  Confidence will be gained and the "fear-factor" will diminish.  Remember asphalt is a tough partner and we are all apprehensive of too close contact. 
•        Find speed and techniques allowing you to ski in control and relaxed confidence.  That may be slow speed, short time and short circuit skiing, but your abilities will rapidly improve.  Parking lots are great.  Remember even the best skiers and athletes of all sports periodically go back and recondition basic skills.  
•        Ski in an area you feel safe; this will allow you to ease up and focus on your skill training.  Along these lines, wear proper and adequate protective equipment. 

Keep training, recover and gradually develop or recondition your skills on rollerskis.  We have many months for development before next ski season.  It is often good to use the rollerskis as supplemental, or one of multiple training modes, rather than as exclusive training tools.  That will allow the body to adapt different motions that complement each other in development and recovery.  Do not forget to hit the gym regularly and with a purpose, and invest a few daily minutes in stretching and other fitness maintenance.

The best of luck,  - j

Jon R. Engen

jonrengen@gmail.com 

xcskicoach.com

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