Description

This study, titled The Leksand Hockey Trial on Grip Strength, aims to explore the relationship between grip strength (GS) and athletic performance in professional ice hockey players. Grip strength is a well-established biomarker for general muscle function, physical capability, and even long-term health outcomes. It is commonly used in sports medicine, rehabilitation, and performance diagnostics due to its simplicity, reliability, and cost-effectiveness. In ice hockey, grip strength plays a particularly critical role given the physical demands of stickhandling, shooting, passing, puck control, and body contact situations.

Despite its relevance, the correlation between grip strength and actual game performance in elite hockey players has not been systematically studied. This project addresses two primary research questions: (1) Does grip strength correlate with performance in professional hockey players? and (2) Does improved grip strength result in measurable performance improvements?

The study will be conducted in two phases. In Phase 1, we will recruit approximately 40 professional male and female hockey players from the Swedish Hockey League (SHL), Swedish Women's Hockey League (SDHL), and HockeyAllsvenskan. Each participant will undergo grip strength testing using the standardized HAKIR protocol with a Jamar dynamometer. Three alternating trials per hand will be recorded, and the average grip strength (in kilograms) will be calculated. Simultaneously, player performance will be assessed based on three key metrics:

Game Score: A composite metric capturing offensive and defensive contributions, adjusted for even-strength playing time (adapted from existing SHL models).

Shots on Goal: Total number of shots per game.

Shooting Precision: Ratio of goals to total shots taken.

Injuries sustained during the season

Each of these metrics will be collected for the five games preceding and following grip strength measurement. Statistical analyses will include Pearson correlation, t-tests, chi-square tests, and non-parametric alternatives where appropriate. Estimates will be presented with 95% confidence intervals, and p-values \< 0.05 will be considered statistically significant. As a pilot study, no formal power calculation will be performed initially, but variance estimates will be used to plan a larger future trial.

Additionally, injuries sustained during the study period will be recorded and monitored as an outcome measure. We will investigate whether there is any correlation between grip strength and injury incidence to assess if stronger grip strength may influence injury risk or resilience in professional hockey players.

In Phase 2, participants will engage in a standardized grip-strength training program over a defined period (see Appendix D). Post-intervention grip strength and performance metrics will be reassessed using the same methods to determine whether an increase in grip strength is associated with performance improvement.

Inclusion criteria include:

Active rostered player in SHL, SDHL, or HockeyAllsvenskan

No current hand or wrist injury

Exclusion criteria:

Not currently signed in the aforementioned leagues

Current injury to the hand or wrist that impairs testing

This project addresses a notable knowledge gap in elite performance research. If grip strength is shown to correlate with or enhance performance, it could be used as a proxy marker in sports performance evaluations and as a justification for implementing targeted grip-strength training in professional hockey conditioning programs. The findings may contribute to improved training strategies, rehabilitation protocols, and performance monitoring in elite ice hockey.