Purpose: The purpose of this experiment was to quantify lumbar muscle endurance training for individuals with a recent episode of acute low back pain (LBP) (≥ moderate pain for ≥ 2 days) and to observe whether the training would reduce the rate and severity of recurrent LBP episodes. Method: Twenty-six participants who were pain-free at the time of the study were randomly divided into a high intensity back endurance (HIBE)-trained or a low intensity abdominal (LOAB)-trained (control) group. The HIBE-trained group performed preloaded maximum isokinetic exertions of the back extensors (five sets of 10 repetitions, 3 days a week for 4 weeks, totaling 12 sessions). The LOAB-trained group performed low intensity isometric contractions on their abdominals that had minimal effect on their back musculature. The two groups reported daily pain logs on a weekly basis on an interactive voice response telephone system for 1 year. Results: The HIBE-trained group experienced more pain days (p = 0.038) in the minor and moderate categories and more episodes of acute LBP than the LOAB-trained group. However, there was a trend of less pain in the severe, intense and excruciating categories in the HIBE-trained group. Conclusions: The results of this experiment did not provide evidence that short-term intense training of the low back musculature provides protection against future episodes of LBP.Implications for RehabilitationShort-term high intensity back endurance (HIBE) training of the back musculature did not provide protection against future episodes of acute low back pain compared to the low intensity abdominal (LOAB) – trained group.HIBE training may have sensitized the subjects to report significantly more minor and moderate pain and less pain-free days compared to the LOAB-trained group.There was a strong trend that the HIBE-trained group experienced less pain in the severe, intense and excruciating categories compared to the LOAB-trained group.Future studies in rehabilitation must require daily recall of pain and quick reporting in order to capture the subtle effects training can elicit from pain reporting.