Latest / Wildlands Podcast — National Parks, Public Lands & Survival / #004 - Field Skills: Altitude | Reading Your Body Above 10,000 Feet

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#004 - Field Skills: Altitude | Reading Your Body Above 10,000 Feet · Wildlands Podcast — National Parks, Public Lands & Survival

• 0:10
  Here is a thing I have watched happen more times
• 0:14
  than I can count. Strong person, fit person.
• 0:19
  Someone who ran a half marathon last month, who
• 0:23
  hiked 30 miles in the Smokies without breaking
• 0:25
  a sweat, shows up at 10 ,000 feet, starts up
• 0:30
  the trail, and by lunchtime, they are sitting
• 0:34
  on a rock with their head in their hands, absolutely
• 0:37
  convinced they are dying. They are not dying,
• 0:43
  but they are not going to the summit either.
• 0:48
  And meanwhile, ten feet away, some guy in cargo
• 0:53
  shorts who looks like he hasn't run since high
• 0:56
  school is whistling past them. Up the switchbacks.
• 1:02
  Altitude doesn't grade on a curve. It doesn't
• 1:05
  care about your Strava stats. It doesn't check
• 1:08
  your gear. Altitude does one thing. It reduces
• 1:13
  the amount of oxygen in every breath you take.
• 1:16
  And your body either keeps up or it tells you
• 1:20
  loudly that it's done. This is Wildlands. I'm
• 1:28
  Sean Spanauer. Know the land before you reach
• 1:33
  it. This is a Field Skills episode, the survival
• 1:39
  curriculum that runs between the park series.
• 1:42
  And this one follows directly from the Great
• 1:45
  Basin Trilogy, because Wheeler Peak tops out
• 1:48
  above 13 ,000 feet. If that mountain is on your
• 1:53
  list, this is the episode you earn it with. We're
• 1:57
  going to cover what altitude actually does to
• 2:00
  your body, what AMS, HACE, and HAPE mean, and
• 2:04
  how to tell them apart, and the rules that let
• 2:07
  you go high and come home. Let's start with the
• 2:11
  physics, because it's simpler than people think.
• 2:15
  And once you get it, everything else clicks.
• 2:19
  At sea level, the air around you is pressing
• 2:22
  down with about 14 .5 pounds of force per square
• 2:26
  inch. That pressure is what pushes oxygen into
• 2:30
  your lungs when you breathe. Every breath, the
• 2:33
  oxygen gets shoved across the thin membranes
• 2:36
  in your lungs and into your bloodstream. Works
• 2:40
  great. You've been doing it your whole life without
• 2:43
  thinking about it. Now go up. As altitude increases,
• 2:48
  atmospheric pressure drops. And here's the thing
• 2:52
  people get wrong. The percentage of oxygen...
• 2:56
  in the air stays the same it's still about 21
• 2:59
  oxygen at 13 000 feet same as at sea level what
• 3:05
  changes is the pressure there's less of it pushing
• 3:09
  that oxygen into you so even though the oxygen
• 3:13
  is there your body can't pull as much of it in
• 3:16
  per breath at the summit of wheeler peak you're
• 3:20
  getting roughly 40 less oxygen into your blood
• 3:23
  with every breath then you would At sea level.
• 3:27
  The air isn't thin. The push is thin. Your body,
• 3:33
  being the stubborn, creative system it is, immediately
• 3:36
  starts trying to compensate. Heart rate goes
• 3:39
  up to push the blood around faster. Breathing
• 3:43
  rate increases. You feel it as extra effort.
• 3:48
  Stares that should be nothing suddenly feel like
• 3:51
  stares that matter. That's normal. That's your
• 3:56
  body doing its job. The question is whether it
• 4:00
  can keep up. And that depends on how fast you
• 4:03
  went up, and how high, and which body you happen
• 4:07
  to be in. Because here's the thing the fit runner
• 4:12
  sitting on a rock needs to understand. Fitness
• 4:15
  does not protect you from altitude. Full stop.
• 4:19
  Your aerobic capacity, your lungs, your heart,
• 4:24
  Your VO2 max. Those are built for earth level
• 4:27
  air. The ability to acclimatize is a different
• 4:31
  system entirely. And it is almost entirely genetic.
• 4:35
  You can be the strongest hiker on the trail.
• 4:39
  And have a body that just doesn't handle altitude
• 4:43
  well. And there is nothing you could have trained
• 4:46
  to change that. And you can be the softest looking
• 4:50
  human at the trailhead. and your body just quietly
• 4:54
  adjusts, barely misses a beat. You don't know
• 4:58
  which one you are until you go up. So, what does
• 5:03
  it look like when your body isn't keeping up?
• 5:07
  That's acute mountain sickness. AMS. And it's
• 5:11
  worth knowing in detail, because it is extremely
• 5:15
  common. AMS almost never shows up below 8 ,000
• 5:20
  feet. but push past 10 or 11 ,000, especially
• 5:24
  fast, and it starts showing up in a lot of people.
• 5:29
  The research suggests that ascending quickly
• 5:32
  to 11 ,000 feet will produce at least some AMS
• 5:36
  symptoms in almost everyone. That's not a fringe
• 5:39
  risk. That's the base rate. The classic picture
• 5:45
  of AMS is simple. Headache. A dull, persistent,
• 5:50
  not -quite -a -migraine headache that arrives
• 5:52
  a few hours after you get to altitude usually
• 5:55
  gets worse if you keep climbing and is often
• 5:59
  worst at night. That headache, combined with
• 6:03
  one or more of the following nausea, loss of
• 6:07
  appetite, fatigue out of proportion to effort,
• 6:10
  dizziness, or lousy broken sleep, and you've
• 6:13
  got AMS. You are not. having a stroke. You haven't
• 6:19
  eaten something bad. Your body is simply behind
• 6:23
  on oxygen and it would like you to stop climbing
• 6:26
  and let it catch up. What do you do? The answer
• 6:32
  is boring but reliable. Stop going up. Rest.
• 6:37
  Drink water. Eat something if you can. AMS at
• 6:44
  the mild stage, the headache, the mild nausea,
• 6:47
  often resolves in 12 to 24 hours if you just
• 6:51
  stay at your current altitude and let your body
• 6:53
  catch up. Ibuprofen can knock down the headache.
• 6:58
  It treats the symptom, not the cause, but it
• 7:01
  lets you rest more comfortably. If you're getting
• 7:04
  better at a given altitude, you can usually continue
• 7:07
  up once you're clear. If you're getting worse,
• 7:11
  go down. Even a few hundred feet of descent can
• 7:15
  make a measurable difference. surprisingly fast.
• 7:19
  The one thing that makes AMS worse every time
• 7:22
  is pushing through it upward. Going higher when
• 7:28
  your body is already behind on oxygen is how
• 7:31
  AMS becomes something much more serious. And
• 7:35
  I want to spend a minute on that because this
• 7:38
  is where people get killed. HACE. High Altitude
• 7:44
  Cerebral Edema. Your brain, swelling with fluid.
• 7:49
  And HAPE, high -altitude pulmonary edema. Your
• 7:54
  lungs, filling with fluid. These are the emergency
• 7:59
  escalations of AMS, and they are not the same
• 8:03
  thing as a bad headache. They are life -threatening,
• 8:07
  and they can move fast. HACE starts to look like
• 8:12
  AMS turned up to 11. A savage headache that won't
• 8:16
  budge, vomiting, confusion, and then the tell
• 8:20
  that should make every alarm go off. Ataxia.
• 8:25
  That's the medical word for loss of coordination.
• 8:29
  The quick field test. Draw a straight line on
• 8:32
  the ground and have the person walk it, one foot
• 8:35
  in front of the other. If they can't, if they're
• 8:39
  lurching, staggering, grabbing for support. That
• 8:43
  is a neurological emergency. Get down. Immediately.
• 8:48
  Don't wait for morning. Don't wait to see if
• 8:52
  they feel better. Down. Now. Hape shows up differently.
• 8:59
  It's in the lungs. So watch for breathlessness
• 9:04
  that's way out of proportion. Even at rest. Even
• 9:09
  sitting still. A dry cough that starts to get
• 9:12
  wet. A bluish tint to the lips or fingernails
• 9:16
  if it's progressing. Extreme fatigue. Chest tightness.
• 9:22
  Hape can kill faster than haste. It sounds terrifying,
• 9:26
  and in the wrong circumstances, it is. The treatment
• 9:31
  for both is the same. Descend. Supplemental oxygen
• 9:36
  if you have it. Get the person to medical care.
• 9:40
  There is no managing haste or hape in the field.
• 9:44
  Down is the only answer. Now, and I want to be
• 9:51
  clear about this, haste and hape are rare in
• 9:55
  the day hiking context. They occur most often
• 9:59
  on multi -day climbs, where people sleep high,
• 10:02
  ascending quickly without acclimatizing. Wheeler
• 10:07
  Peak is a single -day summit from a trailhead
• 10:10
  that's already at 10 ,000 feet. If you're a healthy
• 10:14
  person doing that hike on a day trip, your main
• 10:17
  risk is AMS, not HACE or HAPE. But you need to
• 10:23
  know these exist so that if someone in your party
• 10:27
  is not just tired but actually wrong, staggering,
• 10:31
  confused, blue at the lips, you know what you're
• 10:35
  looking at. And you move. Alright, so how do
• 10:41
  you do this right? How do you go high and not
• 10:44
  get wrecked? The answer is acclimatization. And
• 10:49
  it's simpler than people make it. Your body,
• 10:53
  given time, is genuinely good at this. Over days
• 10:58
  and weeks at altitude, it makes real physiological
• 11:01
  changes. It starts producing more red blood cells.
• 11:05
  to carry oxygen. It adjusts how it regulates
• 11:08
  breathing. The whole system quietly retunes itself
• 11:12
  to work with less push. That's what the people
• 11:16
  who live at altitude their whole lives, Tibetans,
• 11:20
  Andean, Highlanders, have genetically dialed
• 11:24
  in over generations. We're doing the budget version
• 11:27
  of it in a day or two, but even a little bit
• 11:30
  of time matters enormously. The most important
• 11:36
  rule in altitude medicine. Climb high. Sleep
• 11:40
  low. Go up during the day. Come back down to
• 11:44
  a lower elevation to sleep. Your body does its
• 11:48
  biggest acclimatizing work overnight. And sleeping
• 11:51
  lower gives it better air to work with. It's
• 11:55
  the cornerstone of how serious mountaineers structure.
• 11:58
  Weeks on big peaks. And it's directly relevant
• 12:01
  to Great Basin. Why sleeping at Wheeler Peak
• 12:05
  Campground is smarter than driving in from Ely
• 12:08
  and going straight up. One night at 10 ,000 feet
• 12:12
  is doing something. The practical version for
• 12:18
  a Wheeler Peak day hike. Arrive a day early if
• 12:23
  you can. Sleep in the park. Walk around at the
• 12:28
  higher campground. Let your body spend one night
• 12:31
  working on it before you ask it to go to 13 ,000.
• 12:36
  If you can't do that, if you're driving in the
• 12:38
  morning of, then start slow. Start really slow.
• 12:44
  Slower than you think you need to. The mountain's
• 12:47
  not going anywhere. The biggest mistake people
• 12:51
  make is the first mile. Pushing hard because
• 12:54
  the trail is fresh and the legs feel fine. And
• 12:58
  then hitting the wall. Two miles in, when the
• 13:00
  altitude and the effort catch up to them together.
• 13:04
  Hydration. Drink water before you feel thirsty.
• 13:08
  Dehydration makes altitude worse. It thickens
• 13:11
  the blood. It compounds the headache. It accelerates
• 13:15
  the bad timeline. Alcohol the night before a
• 13:18
  high climb is a genuine mistake. Alcohol at altitude
• 13:23
  dehydrates you and suppresses the breathing response.
• 13:26
  your body is already working hard to maintain.
• 13:29
  Save the cold beer for the bottom of the mountain,
• 13:32
  where it belongs. And now the piece I keep coming
• 13:38
  back to, because it shows up in accident after
• 13:41
  accident. The turnaround rule. Before you leave
• 13:47
  the trailhead on any serious mountain, you pick
• 13:50
  a time, not a place, a time, and you commit.
• 13:55
  If I haven't reached the summit by that time,
• 13:57
  I turn around. No exceptions. No negotiating
• 14:03
  with yourself. No, just 15 more minutes. The
• 14:08
  time you set in the parking lot is the boss,
• 14:11
  not the summit. On Wheeler Peak, you want to
• 14:16
  be turning around by noon at the absolute latest.
• 14:21
  Earlier is better. Not because the trail gets
• 14:24
  harder, but because that's when the afternoon
• 14:28
  thunderstorms start building over the high country.
• 14:31
  Lightning on an exposed rocky ridge at 13 ,000
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  feet is not a philosophical problem. It is an
• 14:39
  electrical problem, and you are a conductor.
• 14:44
  The turnaround rule also protects against summit
• 14:47
  fever. That specific flavor of bad judgment.
• 14:52
  where you've invested so much effort to get high
• 14:56
  that turning back feels psychologically impossible
• 14:59
  even when your body is telling you to. Summit
• 15:03
  fever has killed people on every significant
• 15:05
  mountain on Earth, including modest ones. You
• 15:10
  are not immune to it just because you know what
• 15:12
  it is. The time you wrote down in the parking
• 15:15
  lot, before the investment, before the altitude
• 15:19
  started, messing with your thinking. That person
• 15:22
  was making a clearer decision than you are at
• 15:25
  11 ,000 feet with the summit in sight. Trust
• 15:28
  that person. So what does reading your body actually
• 15:33
  look like in practice? Because that's what the
• 15:37
  title of this episode is about. And it's a skill,
• 15:40
  not just a warning. Check in with yourself every
• 15:44
  30 minutes on a high climb. Not just, do I feel
• 15:48
  okay? That question is too easy to answer wrong
• 15:52
  when you're pushing. Ask specific things. Is
• 15:57
  my headache getting better, staying the same,
• 16:00
  or getting worse? Am I breathing hard even when
• 16:04
  I stop moving? Is my pace slower than it was
• 16:07
  an hour ago for no good reason? Am I unusually
• 16:11
  irritable or foggy? That last one is easy to
• 16:15
  miss because the altitude affecting your thinking.
• 16:19
  is the same altitude you're using to assess your
• 16:21
  thinking. This is why you bring someone you trust
• 16:25
  and you actually talk to them. Watch your partners
• 16:31
  too. The person who goes quiet, who starts stopping
• 16:35
  more than usual, who gives short, flat answers,
• 16:38
  check in with them directly. Ask them to walk
• 16:42
  the line. The people who are most in trouble
• 16:45
  at altitude are often the last ones. to say so.
• 16:50
  Pride, stubbornness, not wanting to be the weak
• 16:54
  link, altitude, exploits, all of that. Your group's
• 16:59
  job is to be smarter than any one person's individual
• 17:02
  bad judgment up high. And if the answer to any
• 17:06
  of those check -ins is, this is getting worse,
• 17:08
  not better, that is the only information you
• 17:12
  need. Going down is not failing. Going down is
• 17:18
  the move that lets you come back. Every summit
• 17:21
  I've ever heard someone brag about was a summit
• 17:25
  they came back from. The mountain will be there.
• 17:31
  So that's altitude, how it works, what it looks
• 17:35
  like when it goes wrong, and how to manage it
• 17:38
  so you come home talking about the view instead
• 17:40
  of the helicopter. Quick summary for Wheeler
• 17:43
  Peak or any high summit. Acclimatize at least
• 17:47
  one night at elevation before you go up. Start
• 17:51
  slow and go slower. Drink water ahead of thirst.
• 17:56
  Skip the beer the night before. Know the signs
• 17:59
  of AMS and turn around if it's getting worse,
• 18:03
  not better. Know the signs of HACE and HAPE so
• 18:06
  you recognize a real emergency. Set your turnaround
• 18:10
  time in the parking lot and watch your people.
• 18:15
  Next episode, we're heading to Zion. Part 1.
• 18:19
  The History. From the ancestral Puebloans and
• 18:23
  the southern Paiute who called this canyon home,
• 18:25
  to the Mormon settlers who named it Zion, John
• 18:30
  Wesley Powell, and the building of one of the
• 18:33
  most audacious pieces of engineering in the entire
• 18:35
  national park system. It is a big, rich story,
• 18:39
  and I cannot wait to tell it. I'm Sean Spanauer.
• 18:45
  This has been Wildlands. Know the land before
• 18:52
  you reach it. See you Thursday.