Background: Blood donation-related symptoms such as dizziness, nausea, and fainting are unpleasant for the donor and a significant disincentive for repeat donation. The muscle tensing technique of applied tension (AT) reduced symptoms in several studies.
Study design and methods: This study was a randomized controlled trial of different components of AT. A total of 1209 donors were randomly assigned to one of six conditions involving tension of different muscle groups or donation as usual. Dependent measures included a symptom questionnaire and whether or not the donor's chair was reclined to treat a reaction.
Results: Replicating previous findings, donors who practiced the "full" AT procedure reported significantly fewer symptoms, were less likely to require chair reclining, and rated their chances of giving blood again as greater than those in the donation-as-usual group. Of the component groups, donors who tensed only their lower body were most similar to the full-AT group. Upper-body tension in and of itself did not reduce symptoms though another condition involving upper body tension, which directed attention away from the arm with the needle in it had several significant effects.
Conclusion: The positive effects of AT on blood donation outcome appear to be mediated primarily by lower-body tension though distraction also probably contributes to its impact.