I'm never ill...

I’m never ill, but last month I contracted the first serious upper respiratory tract infection (URTI) I’ve had in years. With perfect timing, my symptoms started two days into my one-week water sports holiday. The “bug” was most likely contracted the on the flight to my holiday destination, but that’s what you get if you spend three hours sealed in a metal tube with 200 kids! My plans to continue my half marathon training were completely scuppered by long (embarrassing) coughing fits and an inability to do anything more energetic than potter about in a dinghy. My lungs felt tight and tender, and I couldn’t even take a deep breath without coughing.

What, you might ask, has all this got to do with “breathing training”? More than you’d think. The experience taught me some very valuable lessons about the effect of inactivity upon inspiratory muscle performance, as well as how much function you can lose, and how long it can take to get it back. I want to share these with you, in case you’re unlucky enough to find yourself in a similar situation, now that we’re heading into winter…

Back to my holiday disaster. To add insult to injury, not only could I not do anything more energetic than sit in a dinghy, I also couldn’t do any IMT, an experience I’ve not had for years, and years, and years…. This situation lasted for 10 long days…

My first challenge upon returning home was attending and speaking at a conference. The day before my presentation I had to rush out of the auditorium five times because of coughing fits – things weren’t looking good for my “big prezo” the next day. However, dosed-up with cough suppressant, I managed a slightly croaky lecture without coughing, and was mighty relieved to get to the end with hardly a splutter.

My next challenge on the road to recovery was my first run. This caused some amusement to the people I passed by, as I coughed uncontrollably with every breath for the first five minutes - I was heckled by calls of “I thought running was supposed to be good for you” , which was almost as funny [not] as overweight teenagers shouting “Run Forrest run”. However, the coughing subsided gradually, and the rest of the run was fairly uneventful, though breathless…until I stopped, when I coughed continuously for another five minutes, but thankfully I was in the privacy of my own home. Then came the biggest challenge, my first IMT session. It was disheartening, to say the least – I couldn’t manage even one breath on my usual training load, BUT thanks to the POWERbreathe® K5 BreatheLink® software I was able to dial the load down “on the fly” so that I could finish the 30 breath session - I needed to drop the load by 16%, but at least I completed the set. However, I was horrified to see the “stats” on my session (I monitor these data daily using the BreatheLink® software) – power down 29%, breath volume down 30%, flow down 20%, total work down 29%. I needed some serious breathing rehab’ if I was to regain the benefits of my years of breathing training! (follow this link for a summary of the many benefits of breathing training)

Here’s what I did to regain my “pumping power”. I did IMT every day, but only once; every other day, I did my IMT after an aerobic workout. I always use the manual load setting on the POWERbreathe® K5, and I increased the training load 2-3 cmH2O each day; however, I also allowed myself to decrease the load during a session if it got too “heavy”, and compromised the quality of the session (i.e., impaired power, flow or breath volume). I found that my “stats” recovered fairly quickly on the days when I did the IMT “fresh”, but on the days were I did an aerobic workout beforehand, the stats took much longer to recover. This indicated that my aerobic workouts had become more fatiguing for my inspiratory muscles (find out why that’s bad news?). In fact, 12 days into my “rehab”, I’m still not quite able to achieve my pre-URTI performance, but I’m getting closer by the day. As for my aerobic training, at first, my pace was slower, and I was more aware of my breathing than I’d been in years, and it’s not a nice feeling! But 12 days on, my pace has recovered, and I’d say I’m back to normal in terms of breathing effort perception – it’s negligible most of the time.

Was the demise of my “pumping power” worse because it was caused by a URTI? Possibly, because the URTI caused ANY increase in flow or volume to induce coughing. However, in my view, any situation that causes a decrease in the activity of the respiratory pump will lead the muscles to detrain. If the cause of this decrease is a musculoskeletal injury, then respiratory pump deterioration can be prevented by maintaining IMT throughout the “lay off”. In fact, if you can do any amount of IMT during a period of illness or injury, you should, because depending upon the duration of the “lay off”, it could take you a couple of weeks to get your breathing back on track.

My experience was salutary for a number of reasons, not least because it gave me a small insight into how much of a “knock back” a respiratory infection can be for a patient with chronic lung disease (and I didn’t even have a lower respiratory tract infection). It also confirmed what is known about detraining of inspiratory muscles from patients who need to be mechanically ventilated – in their case, the inspiratory muscles are essentially switched off, and a pump forces air into their lungs – in my case, my inspiratory muscles experienced a dramatic decrease in their physical activity. In both cases, inspiratory muscle function appears to fall off a cliff!

What else have I learnt? It’s staggering how quickly “you lose it” when “you don’t use it”. In my case, my inspiratory muscles had virtually no exercise AT ALL for 10 days – no aerobic-related work, and no IMT (my expiratory muscles were kept in fine fettle by my coughing fits!). The good news is that I’ve been able to recover almost all of my lost function in the 12 days that followed the URTI. The keys to this were: doing IMT every day; allowing myself to decrease my normal training load to maintain “reps” and training quality; being aware that my IMT would be more affected than usual in a pre-fatigued state (i.e., after an aerobic workout) and adjusting my load accordingly; increasing the training load slowly, but surely each day.

When it comes to the inspiratory muscles, the “use it or lose it” phenomenon appears to be particularly potent. This probably reflects the fact that, under normal conditions, the inspiratory muscles are active from our first to our last breath. This seems to make them extremely sensitive to changes in the demands that are placed upon them – wasting away quickly when demand decreases. However, the reverse is also true, and with the right training stimulus, it’s possible to increase function quickly and substantially.