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Abstract Background This study aimed to determine whether sex, hand length and the individual training status affect hand strength and whether these measurements differ if they are recorded using the Jamar dynamometer or a new cylindrical measuring system. Methods For this purpose, 152 healthy adults were examined using a new manugraphy measuring system (novel, Munich, Germany) comprising two measuring cylinders of different sizes and a Jamar electronic dynamometer with two grip positions corresponding approximately to the sizes of the cylinders. A descriptive analysis was performed as well as a correlation analysis using the Pearson correlation coefficient. To prepare predictive models, multiple linear regression analyses were carried out to determine factors that influence the force and p ≤ 0.05 was considered statistically significant. Results A significant difference in the maximum and mean strength was observed that is dependent on sex, with men stronger than women, in line with expectations, and hand length, with small hands able to exert less force than large hands. No consistent increase in strength could be attributed to repetitive manual loads applied either at work or in leisure activities. Conclusions Both measurement techniques yielded similar results, suggesting that manugraphy is well suited for clinical research purposes because it not only takes measurements that are just as reproducible and valid as the conventional measurement technique but in doing so measures not just the total strength of a hand but also enables more precise comparisons of isolated hand regions applying dynamic measurements.

Background: This study aimed to determine whether sex, hand length and the individual training status affect hand strength and whether these measurements differ if they are recorded using the Jamar dynamometer or a new cylindrical measuring system.Methods: For this purpose, 152 healthy adults were examined using a new manugraphy measuring system (novel, Munich, Germany) comprising two measuring cylinders of different sizes and a Jamar electronic dynamometer with two grip positions corresponding approximately to the sizes of the cylinders. A descriptive analysis was performed as well as a correlation analysis using the Pearson correlation coefficient. To prepare predictive models, multiple linear regression analyses were carried out to determine factors that influence the force and p ≤ 0.05 was considered statistically significant.Results: A significant difference in the maximum and mean strength was observed that is dependent on sex, with men stronger than women, in line with expectations, and hand length, with small hands able to exert less force than large hands. No consistent increase in strength could be attributed to repetitive manual loads applied either at work or in leisure activities.Conclusions: Both measurement techniques yielded similar results, suggesting that manugraphy is well suited for clinical research purposes because it not only takes measurements that are just as reproducible and valid as the conventional measurement technique but in doing so measures not just the total strength of a hand but also enables more precise comparisons of isolated hand regions applying dynamic measurements. [ABSTRACT FROM AUTHOR]

This study developed a methodology to examine the effects of grip size and grip firmness on the kinematic contribution of angular velocity (KCAV) to the generation of racket head speed during a topspin tennis forehand. The KCAV is subdivided into kinematic contribution of joint angular velocity and kinematic contribution of the body segments in the upper trunk translational and angular velocities. Two Babolat Pure Storm GT rackets, with grip sizes 2 and 4 respectively, were used with Tekscan 9811E pressure sensors applied to the handles to examine pressure distribution during the stroke. Upper body kinematic data taken from the racket arm and trunk were obtained by means of a Vicon motion capture system. One elite male tennis player was recruited. Fifty topspin forehand strokes per grip at two nominal grip pressures were performed in a laboratory environment with balls being tossed towards the player and struck on the bounce towards a target on a net in as consistent a way as practically achievable. Processing of the results showed that the firm grip condition led to a significant (p<0.001) increase in average racket head speed compared to a normal grip condition. The normal gripping condition resulted in a significant (p<0.001) increase in average racket head speed for grip size 2 compared to grip size 4. A trend in negative linear relationships was found between upper trunk and shoulder joint in KCAV across conditions. Using the smaller grip also led to a trend in negative linear relationship between shoulder joint and wrist joint in KCAV across grip conditions. Grip pressure for grip size 2 showed the same pattern across gripping conditions. From 50-75% of completion in forward swing, the pressure difference due to grip firmness decreased. This feasibility study managed to quantify the KCAV while performing a topspin forehand, with respect to changing of grip size and grip pressure in an elite male tennis player for the first time. [ABSTRACT FROM AUTHOR]

Background: Grip size of a tennis racquet has been reported to influence performance, but clear evidence of a correlation has yet to be established.Hypothesis: Hitting force during a soft tennis forehand stroke correlates with grip size.Study Design: Controlled clinical study.Methods: A total of 40 healthy volunteers (20 men and 20 women) with a mean age of 21.9 years were enrolled. Of the 40 participants, 20 were experienced soft tennis players (10 men and 10 women) and 20 were nonexperienced soft tennis players (10 men and 10 women). Based on racquets with 5 different grip sizes, the hitting force during a soft tennis forehand stroke was measured with a handheld dynamometer. Correlations between 4 factors (sex, experience, grip and pinch strengths, and middle finger length) and hitting force were evaluated with each grip size. Measurements for each factor were repeated, and a 2-way analysis of variance was performed on the obtained data.Results: The hitting force was greater for male players than for female players and greater for experienced players than for nonexperienced players (P < .01). Men with large grip and pinch strengths demonstrated an increased hitting force with an increase in grip size. Men who had a long middle finger also demonstrated increased hitting force when grip size increased (P < .05).Conclusion: The hypothesis proved accurate for experienced men who had a large grip strength, a large pinch strength, and a long middle finger.Clinical Relevance: Large-grip-sized racquets may result in better forehand stroke performance when used by experienced male soft tennis players with a large grip strength, a large pinch strength, and a long middle finger. [ABSTRACT FROM AUTHOR]

Background: Inappropriately sized tennis racket grip is often cited in the popular media as a risk factor for overuse injuries about the forearm and elbow. Currently, a hand measurement technique developed by Nirschl is commonly used by tennis racket manufacturing companies as the method for determining a player's ‘recommended’ grip size. Hypothesis: Quarter-inch changes from that recommended by Nirschl in tennis racket grip size will have no significant effect on forearm muscle firing patterns. Study Design: Controlled laboratory study. Methods: Sixteen asymptomatic Division I and II collegiate tennis players performed single-handed backhand ground strokes with rackets of 3 different grip sizes (recommended measurement, undersized 1A in, and oversized ¼ in). Fine-wire electromyography was used to measure muscle activity in extensor carpi radialis longus and brevis, extensor digitorum communis, flexor carpi radialis, and pronator teres. Repeated-measure analysis of variance was used for within-group comparisons, comparing different grips in specified phases for backhand ground strokes (P≤.05). Results: There were no significant differences in muscle activity between small, recommended, or big grips in any muscle tested. Conclusion: Based on these findings, tennis racket grip size ¼ in above or below Nirschl's recommended measurement does not significantly affect forearm muscle firing patterns. Clinical Relevance: Alterations in tennis racket grip size within ¼ in of Nirschl's recommended sizing do not have a significant effect on forearm muscle activity and therefore may not represent a significant risk factor for upper extremity cumulative trauma, such as lateral epicondylitis. [ABSTRACT FROM AUTHOR]

The article presents a study that focuses on the comparison between the isometric grip strength and precision with the use of rackets of increasing grip size in prolonged simulated match. It indicates the measurement of maximal voluntary isometric contraction (MVIC) before and after the match. The study shows that the loss of handgrip MVIC depends on the grip size of the racket.