Year: 2024  Country: Finland   Study Population: N=15 healthy volunteers

Wahlroos N. Predicting one repetition maximum from the results of isometric strength tests. Turku University of Applied Sciences. Bachelor’s Thesis; 2024. 

Objective

The study aimed to determine whether maximum voluntary isometric contraction (MVIC) values could be reliably converted into one repetition maximum (1RM) values in order to develop a mathematical formula for the conversion. A secondary aim was to examine the relationship between 1RM and isometric muscle strength measured with David exercise devices.

Methods

The study participants comprised of healthy, trained men (n = 6) and women (n = 9). 1RM and MVIC tests were carried out at the Nordic Health clinic located in Helsinki. Data was collected from 20 different exercises using David exercise devices. A linear regression analysis of the participants' 1RM and their isometric test results was conducted. Zero points (0Nm/0Kg) were added manually to improve accuracy on low isometric test results. The results of this analysis were inserted into the standard regression formula. Based on this, a device-specific formula was created for each device.

Outcome

As a result of this thesis, a strong correlation between 1RM and MVIC values was found (0.89). Additionally, a device-specific formula to estimate a person’s 1RM based on the results of the isometric muscle strength measurement was developed