The Effect of Hand Dominance on Finger Strength

1. The Effect of Hand Dominance on Finger Strength Mackenzie Abate

2. Problem/Rationale • Who has stronger fingers: the left-handed or the right-handed person? • Whose non-dominant hand is stronger?

3. Research • Muscle in the hands and fingers • Voluntary • Muscle fatigue • Lactic acid build up • Can be used to measure strength in hands and fingers • Force in Newtons • The fingers are tested by placing each finger on the respective pad and their thumb on the base. • Each finger is tested except the thumb which is the base. Skeletal Muscle Vernier Hand Dynamometer

4. Research • Muscle Fatigue • Decrease in performance • Fatigue at the muscle site • Muscle is not getting enough oxygen from the blood • Lactic acid builds up and renders the muscles unable to perform • Messages from the nervous system • The brain tells the muscle to stop working • This is to avoid tearing

5. Hypothesis • It was hypothesized that right-handed people will have greater and longer lasting finger strength. Those who are left-handed will have the advantage when it comes to their non-dominant hand and the fingers on their non-dominant hand will have a greater and longer lasting strength.

6. Procedure • A survey was given out. • 11 subjects were picked from this survey: five dominantly left handed, five dominantly right and one ambidextrous. • Each subject completed a baseline test for each hand. • The strength of each finger was tested on both hands with a 10 second interval test. • The durability was tested next in which the subject’s finger strength was held for a maximum amount of time possible for both hands. • Data was measured in Newtons.

7. Data This data table shows the percent change in strength in both tests and time in the second test between the ambidextrous subject’s dominant and non-dominant hands.

8. Data

9. Data

10. Data

11. Discussion • The hypothesis was not supported by the data. • In the ten second test, most of the right-handed subjects’ non-dominant hands were a little stronger, and the left-handed and ambidextrous subjects’ non-dominant hands were weaker. • In the second portion of the test, both lefties’ and righties’ dominant hands were able to sustain a grip for longer than their non-dominant hand.

12. Discussion • Possible Error • Small pool of people who all participate in various different activities • Subject 9 had surgery to repair torn ligaments in her wrist about a month prior to being tested. • Each subject interpreted the instructions differently for the second test. • Improvements • A better explanation of the instructions would be given. • All subjects would be involved in the same activities, if any. • They would all be in their best condition meaning no recent surgeries or injuries

13. Conclusion • Do right-handed or left-handed people have stronger fingers? Whose non-dominant fingers are stronger? • Typically, lefties have stronger fingers on their dominant hand while righties have stronger and more durable fingers on their non-dominant hand.

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