Vernier does sell a Dual-Range Force Sensor (DFS-BTA), and a Go Direct^® Force and Acceleration Sensor (GDX-FOR), that can be used for this application. We have not tested these sensors in-house, but several college professors have told us that they can work well for the standard frog muscle lab.

The DFS-BTA has a range of +/-10 N and +/-50 N. Most physiologists use force sensors that report in grams. On the most sensitive setting, the DFS-BTA has a range of +/- 1 kg.

The best solution is likely the Go Direct^® Force and Acceleration Sensor (GDX-FOR), as it can resolve forces of +/- 0.1N or about 1g of force.

Frog leg twitches vary in amplitude, but they are typically in the 10-20 g range. The Dual-Range Force Sensor and Go Direct Force Sensor are sensitive enough for this application.

Frog heart contractions usually generate forces that are less than 1 g in amplitude. The typical force from a frog heart can be 0.2 g in amplitude and can vary. The DFS-BTA and GDX-FOR are not sensitive enough for this application.

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How can I use Vernier products to study muscle activity?