Hypothetical question for any PT
Suppose you were a physical therapist who was interested in determining if a new ACL rehabilitation technique helped soccer players regain their pre-injury performance levels more quickly than existing ACL rehabilitation techniques. For your research, you utilize a pre/post test of 1RM knee extension (using an isokinetic device) and, for your intervention, soccer players with the same ACL injuries are rehabilitated with either the new technique or an older, existing technique. Your results show that players who rehabbed with the new technique had a significantly higher 1RM than the old technique group after 6 weeks of rehabilitation.
In addition, the 1RM of the new rehab group appeared to be almost the same as pre-injury levels.
However, when these same players attend their first soccer practice, it is clear that both the old and new groups perform equally well (with respect to their soccer skills).
In other words, your research suggested one technique was superior but this did not hold true in the actual soccer setting.
What could you have done differently to ensure your results were a more accurate reflection of soccer performance?