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In the original research on frail elderly individuals, the study often cited for remarkable strength gains through knee extensions began with three sets of 8 repetitions per session. This allowed for manageable intensity while still stimulating strength improvements.

The protocol typically followed these principles:

Start with a manageable weight (often around 20-30% of maximal effort).
Perform three sets of eight repetitions with controlled movements. Gradually increase resistance as your strength improves—progression is essential. If you experience fatigue or discomfort early on, it's advisable to start with fewer repetitions and build up gradually. The goal is to focus on proper form and consistent progress.