In the 1980s, Ken worked in intensive care units, where patients often suffered weaning off ventilators. He also worked with ex-coal miners who had pneumoconiosis as well as COPD. Respiratory conditions for these patients were compounded by atrophy of breathing muscles from disuse.

Doubtful that the maximal effort of threshold devices would ensure an improved response, he used a pen recorder to study the one-second Maximum Inspiratory Pressure (MIP). That initial endeavor used a pressure gauge from a central heating system.

Based on these results, Ken developed a training and assessment tool based on the maximal effort that extended the traditional MIP measure to an isokinetic-resisted inspiration from residual volume (RV) to total lung capacity (TLC).

The Test of Incremental Respiratory Endurance (TIRE) protocol was developed as a bedside measure of inspiratory muscle endurance and a through-range inspiratory muscle training protocol.

Ken’s vision for widespread progress in respiratory health and fitness became a reality when his limited access desktop version (RT2) became a portable, cost-effective healthcare solution called the PrO2—the first to use full-breath resistive RMT in the United Kingdom.

In 2014, PrO2Health was formed to make the successor product - the PrO2. The PrO2 became the first RMT device that paired with smart phones to gather data, upload it to the cloud and provide access for trainers and clinicians. Since being released, dozens of studies, thousands of users and millions of breaths have been logged.