Increase Your Open Water Swim Comfort level

Triathletes often describe the sensations that they interpret as an attack: shortness of breath, tightness in the chest, dizziness, light-headedness and strong self-talk. Symptoms of a panic attack, according to the American Psychological Association (APA), sound similar: 

• Racing heartbeat 
• Difficulty breathing, feeling as though you ‘can't get enough air’ 
• Terror that is almost paralyzing 
• Dizziness, lightheadedness or nausea 
• Trembling, sweating, shaking 
• Choking, chest pains 
• Hot flashes or sudden chills 
• Tingling in fingers or toes (pins and needles) 
• Fear that you're going to go crazy or are about to die 

However, there are some important differences. Again, according to the APA: “A panic attack is a sudden surge of overwhelming fear that comes without warning and without any obvious reason.” 

The main different here is “without any obvious reason.” In the case of open water swimming, there could be some very obvious reasons. 

For starters, let’s see if perhaps there aren’t physiological rather than psychological causes.

One way to induce the symptoms some swimmers feel is a tight collar. On either side of your neck you have a carotid artery. Inside the carotid artery below your jawline is the carotid body, a small area that includes pressure sensors. Pressure on the carotid body increases blood pressure, which then signals your heart to slow down. Your carotid body sends this signal to your heart via the vagus nerve, which will become even more important later in the story. 

This carotid sinus reflex is sufficiently dependable that doctors sometimes use mild pressure on the carotid sinus to reduce heart rate in patients whose hearts are beating too fast. According to Selvin and Howland (1961), males older than 50 years and with high blood pressure can be disproportionally susceptible to carotid sinus reflex. 

The location of carotid body, high up on your neck under your jaw, is well out of the way of most collars on wetsuits specifically designed for swimming. However, neoprene swim caps with a chin strap may get close to this area of your neck. 

One of the easiest things to do to avoid all those icky feelings: make sure that nothing much is pressing on your neck. 

Before you don your wetsuit, try putting a plastic grocery bag on your foot, then slip into the leg of your suit and when your suit is all the way on your leg and your foot protrudes, pull off the bag. Repeat with the other leg and both hands. The slippery plastic bag helps your limbs slide into your suit effortlessly and completely, to get your legs and arms well into the suit. Make sure you create a little gather of neoprene at the front of your shoulder to avoid having any tension on your collar. Once you are in your suit, pull the collar away from your throat.

A second physiological phenomenon that can cause similar symptoms is a result of you being a mammal. Maybe you have seen stories of children who fall through the ice and get rescued many minutes afterward being submerged, only to recover fully. All mammals have this natural ability, called the mammalian diving reflex (DR), to respond to submersion. 

It works like this: 
When you put your face in cold water and hold your breath, the trigeminal nerve in your face sends a signal to your vagus nerve (there’s the vagus again) to slow down your heartbeat. Your body also shunts blood flow from your extremities to your internal core and brain. 

You could imagine this conversation: 
“Hey, wait wait wait wait! I feel cold water and pressure on my face and I’ve stopped breathing!” 
“What do you think this means?” 
“What, are you dense? We are drowning!” 
“What should we do?” 
“OK, well first let’s slow down the heart rate and ship more blood to the brain, so we can keep that going at least and conserve as much as we can until we surface.” “Hey, good idea.” 

This mammalian diving reflex is just fine for keeping you from dying too fast underwater, but it really feels inconvenient when you are trying to swim. You slip into the water, and it’s cold. For the purposes of your trigeminal nerve, anything in the 70s and below (F) qualifies as cold. As you start to swim, your mammalian diving reflex kicks in, your vagus nerve reduces your heart rate and your blood departs your extremities. 

But also when you start your swim, another part of your system wants to elevate your heart rate and flush your swimming muscles with blood. 

When you jump into cold water and swim away, if you feel as though you have a war going on in your chest, you are not far off. According to Rennie (2012) “A disadvantageous consequence, however, is that the muscles in the limbs must then rely more on anaerobic energy metabolism to keep working, so they build up lactic acid and tire more rapidly than they would from comparable exercise at the surface.” Maybe this feels true to you. And according to Panneton (2013),“The DR is the most powerful autonomic reflex known.” He goes on to say, in laboratory experiments, “100 percent of rats get it 100 percent of the time.” 

You are dealing with very strong forces here. 

Fortunately again, there is an easy solution to the mammalian diving reflex war in your chest. 

Recall your first swim lesson — blow bubbles. 

Even before you start your swimming warm-up, you might consider doing your breathing warm-up. You do this by bobbing in the water. Yes, bobbing. As in, bobbing up and down. The easiest way to prevent that feeling is to warm up a little before you swim off. 

1. Get in the water. Let the water trickle into your wetsuit. Float around for a few moments and feel the temperature of the water on your hands, feet, face and head. Adjust the collar of your wetsuit off your neck to make sure that your wetsuit is not pressing on your carotid arteries. 
2. Bob. Take a breath. Put your face in the water and in a relaxed way exhale bubbles for 10 or 15 seconds. Lift your face into the air, take in a relaxed breath and then bob again. Repeat this for perhaps a minute or two. 
3. Swim a little. Do some 25- or 50-meter easy swimming back and forth along the shoreline to get your muscles and your heart on the same page. 
4. Go swim. 

By gently bobbing for perhaps a whole entire minute before you start swimming, you settle down your trigeminal-vagus nerve cascade, get your inner mammalian diving reflex part to realize that indeed you are not drowning and you can just calm down. Then you can settle into your swim warm up and carry on. 

Those two physiology issues, carotid sinus reflex and mammalian diving reflex, can explain a lot of that panicky feeling. Let’s get back to psychology for a moment. 

One of the things about panic attacks: they can lead to altered behavior. Most important is to avoid developing panic attacks by attending to the physical causes and gaining the calmness in the water that makes open water swimming so rewarding.

• APA. Panic attacks: the hallmark of panic disorder. Retrieved from http://www.apa.org/topics/anxiety/panic-disorder.aspx 
• Panneton, W. Michael. (2013). The Mammalian Diving Response: an enigmatic reflex to preserve life? Physiology: 28(5) p. 284-297 
• Rennie, J. (2012). How the dive reflex extends breath-holding. Scientific American, March 22, 2012 
• Selvin, B and Howland, WS. M.D. (1961). New concepts of the physiology of the carotid sinus reflex. Journal of the American Medical Association. 1961;176(1):12-15. doi:10.1001/jama.1961.03040140014004. 

Will Murray is a USA Triathlon Certified Coach and is the mental skills coach for D3 Multisport. He is co-author, with Craig Howie, of “The Four Pillars of Triathlon: Vital Mental Conditioning for Endurance Athletes.”