Acute Effects of High Intensity Training on Pain Processing and Inflammation in Chronic Low Back Pain.

During the high intensive cardiorespiratory exercise protocol, a bicycle ergometer (eBike Basic, General Electric GmbH, Bitz, Germany) with pulmonary gas exchange analysis (MetaMax 3B, Cortex Biophysik GmbH, Leipzig, Germany) will be used. Oxygen uptake (VO2max), expiratory volume (VE) and respiratory exchange rate (RER) will be tracked every breath and an average will be taken every 10s. Heart rate is continuously monitored using a heart rate chest strap (Polar Electro Inc., Finland). After a five-minute warm-up, a high-intensity interval protocol is started, consisting of five one-minute bouts (110 reps/minute at 100% VO2max workload), separated by one minute of active rest (75 reps per minute at 50% VO2max workload).

During the moderate intensive cardiorespiratory exercise protocol, a bicycle ergometer (eBike Basic, General Electric GmbH, Bitz, Germany) with pulmonary gas exchange analysis (MetaMax 3B, Cortex Biophysik GmbH, Leipzig, Germany) will be used. Oxygen uptake (VO2max), expiratory volume (VE) and respiratory exchange rate (RER) will be tracked every breath and an average will be taken every 10s. Heart rate is continuously monitored using a heart rate chest strap (Polar Electro Inc., Finland). After a five-minute warm-up, participants begin a moderately-intensive continuous 14-minute exercise protocol at a stable resistance (90 repetitions per minute at 60% VO2max workload).