TL;DR
If you're an ultraendurance athlete then you should spend three quarters of your time just below your Aerobic Threshold and most of the rest just below your Anaerobic Threshold. Everyone benefits from a little strength training.
What it Takes to Climb a Mountain
There are three components to climbing a mountain. You need the right skills, the right equipment and the right body. Training for the New Alpinism: A Manual for the Climber as Athlete by Steve House and Scott Johnston is about how to build the optimal body for alpine mountaineering.
Training for the New Alpinism is among my favorite books on athletic training. It has great information on subjects from altitude acclimation to "whether Peanut M&M's are in fact nature's most perfect food", but my favorite chapters are endurance conditioning[1] and physiology[2].
Training for the New Alpinism is concerned with an athlete's ability to exert force. In this context, physical conditioning has four components.
- Muscular strength is the peak force you can exert with your muscles.
- Muscular endurance is how much force you can exert from your muscles for a medium length of time.
- Aerobic endurance is how much power you can sustain for a long period of time.
- Speed is how fast you can operate your muscles.
Peak Speed Doesn't Matter
[S]peed is not only very genetic, it’s very very hard to train. It takes constant, relentless work to get small improvements (consider that a track sprinter may train for a year to take a tenth [of a second] or less off their best time).
―All You Need to Know About Training by Lyle McDonald
Speed is measured in fractions of a second. Mountain climbs are measured in days.
Muscles are Heavy
Increasing your strength has two phases. At first, your body will increase muscle recruitment. This is a neurological adaptation. It adds no weight. Muscle recruitment strictly adds to your endurance because it spreads your exercise load across more muscle fibers who take turns contracting which increases how long it takes to exhaust each individual muscle fiber.
A minimum muscular strength is necessary to climb a particular mountain. If you have good muscle recruitment then additional strength gains are counterproductive to mountain climbing because increasing strength (beyond muscle recruitment) increases your weight. Carrying extra weight makes it hard to climb mountains. A specialized mountaineer builds no more muscle than he or she needs.
Muscular strength is a precondition to muscular endurance. Alpine mountaineers build a little bit of muscle mass and then extract as as much muscular endurance as they can out of it. According to the authors, "You'll do it via very sport-specific movements in workouts using up to hundreds of repetitions."
Aerobic Endurance Zones
Endurance is the most important attribute of an alpine mountaineer. The authors quantify effort by bucketing heart rate into six zones. The heart rate (HR) percentages are rough guides. What really matters is the state changes.
Recovery Zone (<55% of max HR)
Light exercise speeds recovery when compared to sedentary activity "because aerobic enzymes and hormones…actually improve the rebuilding process of the structures damaged during harder training" but the exercise isn't hard enough to actually damage the structures.
If you're exercising so hard that you're no longer recovering that means you have entered Zone 1.
Zone 1: Basic Endurance (55-75% of max HR)
This is often referred to as a "conversational pace." You will be able to speak in complete sentences with your training partner, and the pace should feel relaxed and easy. To find the upper end of this zone, start by exercising slowly while breathing through your nose only. As you increase the intensity/speed gradually, note the point at which this nose breathing becomes noisy and labored. This is the upper end of Zone 1.
This reference point corresponds to what exercise physiologists call the Aerobic Threshold (AeT). For reference: During a treadmill step test this would be the point at which the level of blood lactate would have risen above its baseline amount. Aerobic threshold power output is the single most important measure of a person's aerobic system. This is the single most important measure of endurance for an alpine climber.
―Training for the New Alpinism
I think of Zone 1 as the pace you can sustain all day.
Zone 1 the most important attribute of a mountaineer because climbing a mountain takes multiple days. Mountaineers should spend most of their time training in Zone 1 because the way to get better at Zone 1 endurance is to train in Zone 1. Zone 1 is very light. To get the most out of this training, mountaineers compensate with volume. Optimal training requires an average of at least two hours of Zone 1 training per day, everyday.
Even the world's elite endurance athletes spend more than three-quarters of their training volume at this low intensity, so do not let its ease fool you into thinking it does not offer significant training benefits…. This zone has the least reliance on specificity so a variety of training modalities such as climbing, approaching climbs, hiking, and running can be used with decent results. This allows for increased volume without overuse and boredom.
―Training for the New Alpinism
My preferred method of Zone 1 training is to ride my bicycle to a mountain and then climb the mountain. Zone 1 feels good. It's one reason why bicyclists smile so much. (The other reason is Zone 3.)
The Aerobic Threshold (AeT) describes the boundary between Zone 1 and Zone 2. Recall from the introduction that most of your training should take place right below the AeT.
Zone 2: No Man's Land (75-80% of max HR)
Zone 2 is too easy to be useful and too hard to justify the effort. Amateur athletes frequently train in Zone 2 because it's what they think training is supposed to feel like even though Zone 2 is precisely the opposite. No Man's Land is where you suffer unnecessarily, make lots of noise and ultimately accomplish nothing.
Zone 3: Upper Aerobic Training (80-90% of max HR)
Zone 3 provides uses half aerobic and half anaerobic energy.
This is the range for much of the hard training you do. It is not a hard kind of hard. It is more of a fun kind of hard. It is an effort level that makes you want to say, "Oh yeah! Bring it on! I feel strong." It should feel good to go at this intensity. In fact it is this addictive good feeling that causes many athletes to spend too much of their training time in this zone.
―Training for the New Alpinism
Zone 3 is not peak speed.
In Zone 3, you should still feel like you have another gear that you could shift into to go even faster at any time should you desire. If you don't have that feeling, then you are actually in the higher-intensity Zone 4 and going too hard to elicit the training benefits we seek. In Zone 3, harder is definitely not better. This is not exhausting maximal work. This is a pace you could sustain for an hour. When you reach the upper end of this level of intensity, your breathing will take a jump upward that won't allow you to speak in complete sentences but only utter a couple of words at a time.
The boundary between Zone 3 and Zone 4 can be called the Anaerobic Threshold (AnT) or the Lactate Threshold (LT). Be careful not to confuse the AnT with the AeT. The AeT marks the boundary between Zone 1 and Zone 2. The AnT marks the boundary between Zone 3 and Zone 4.
Zone 4: The Anaerobic Zone (90-95% of max HR)
This mix of hard aerobic and anaerobic training is sometimes referred to as VO₂ max training because studies have shown that for well-trained endurance athletes this intensity can have the most beneficial effect on improving the maximum aerobic power. Make no mistake, this is hard training and the pace is sustainable only for a few minutes before you will be forced to slow down. An interval method of training is usually used since it allows for repeated efforts at the hard intensity necessary to affect the desired adaptations….
Your breathing in this zone will not allow more than a word or two being gasped out, and when you stop you'll be breathing about as deeply as you can. The classic pose for athletes having finished an effort like this is bent at the waist with hands on knees supporting the upper body and breathing very deeply and rapidly.
―Training for the New Alpinism
Zone 4 has costs and benefits. The benefit is it increases your VO₂ max. The disadvantage of Zone 4 training is it trains your anaerobic energy pathways more than your aerobic energy pathways. A mountaineer's Zone 4 training must be balanced against a large aerobic base developed in Zone 3 and (mostly) Zone 1.
For this zone to produce the best results in terms of increasing your aerobic power, many top coaches carefully limit the amount of high-intensity (Zone 4) training they prescribe until they see their athletes' aerobic threshold pace come to within 10 percent (or even 5 percent for world class) of the pace they can sustain at their personal anaerobic threshold. Only then can they be assured that the aerobic system has the base to support this higher-intensity work.
―Training for the New Alpinism
That "10 percent" is for athletes like marathon runners. Alpine mountaineering makes marathon running look like a sprint. VO₂ max matters little to alpine mountaineers whose event durations are measured in days and weeks rather than hours.
Alpine mountaineers do not need Zone 4 training.
Zone 5
Zone 5 is strength training. It is purely anaerobic. A little bit of Zone 5 training first increases muscle recruitment. Additional Zone 5 training builds muscle. Muscle recruitment increases endurance without building muscle. In this way, at least a little bit of strength training is useful to all alpine mountaineers, including those who do purely nontechnical endurance-oriented climbs like Mt Rainier.
It can be very difficult for most women to gain appreciable muscle mass, especially in the upper body, even with specialized training. This being said, it will benefit women with high athletic goals to spend some of their precious training time and energy focusing on a Max Strength plan, because it will help with injury prevention as well as making them stronger climbers…. Much of a woman's strength increases will come about due to the neurological adaptations mentioned above.
The cruel fact remains that a female alpinist's pack is going to weigh just as much as her male counterpart's. This makes it all the more imperative for her to improve her strength-to-weight ratio.
―Training for the New Alpinism
The information on endurance training is so good it was used by lots of athletes in adjacent endurance sports. In response to all the positive feedback, the authors wrote a second book for mountain runners and ski mountaineers. ↩︎
This article summarizes the the endurance section. If you want to understand the physiology underlying these training methods, I recommend reading the book. ↩︎