Dear GoBlog, in lieu of really good steroids or an injection of Dex, what can I do to improve performance? That's a great question faithful blog reader. Other than exercising really, really hard, how about using the Powerbreathe hand-held inspiratory muscle trainer? It's the official Ironman "inspiratory muscle trainer" dontcha know! Inspiratory muscles you ask? Yeah, well, evidently they're the ones you use to breath and exercising them can boost your performance:

Research has shown that the inspiratory muscles have such a huge task to perform that they can 'steal' blood from our exercising limbs to supplement their work (Harms et al., 1998). The effect of this is to limit the performance of those limb muscles - making exercise feel harder and impairing performance. New research has now shown that specific inspiratory muscle training (IMT) improves the efficiency of the inspiratory muscles (Sharpe & McConnell, 1998), with the consequence that performance in laboratory controlled trials is improved by almost 30% (Caine & McConnell, 1998).

Read more on the Powebreath site. Beats buying a barometric chamber we suppose.