Sage Journals: Discover world-class research

Abstract

Objective:

The aim of this study was to analyze finger strength and effects of muscle fatigue on the ability to shoot.

Background:

The finger and hand muscles of soldiers are subject to high loads. For example, the trigger pull of military pistols can amount up to 58 N (≈6 kg) and could cause muscle fatigue in the trigger finger. For soldiers, however, maintaining the ability to shoot is essential for self-defense and survival.

Method:

The marksmanship training of 30 German soldiers (15 female) ages 18 to 40 years was evaluated. Three consecutive exercises with a total of 60 rounds were fired from target ranges of 5 and 10 m, equally using a single-action and double-action trigger mode. Maximum voluntary isometric contraction of the index finger (MVC_IF) was measured before and after each of the three firing exercises.

Results:

Shooting reduced MVC_IF in female (88.2 ± 15.8 N to 67.3 ± 17.7 N, p < .001) and male soldiers (145.8 ± 21.7 N to 112.7 ± 26.6 N, p < .001). Of the 30 subjects, 23 were unable to shoot due to fatigue, including 15 of 15 female soldiers. The higher MVC_IF was at rest, the less commonly (r = .73, p < .001) and the later (r = 0.82, p < .001) task failure occurred. Two intermissions of approximately 6 min did not suffice for a significant recovery.

Conclusion:

Excessive trigger pull weight causes muscle fatigue of the index finger and can ultimately lead to task failure during pistol marksmanship training. Short breaks are insufficient for the recovery of finger muscles.

Application:

This study presents a new perspective on ideal trigger pull weight, which should be carefully considered by manufacturers to allow repetitive firing and simultaneously ensure safe handling.

Keywords

index finger upper extremity gender physical ergonomics task analysis

Get full access to this article

View all access options for this article.

References

Allum

J. H.

Dietz

Freund

H. J.

(1978). Neuronal mechanisms underlying physiological tremor. Journal of Neurophysiology, 41, 557–571.

Anderson

G. S.

Plecas

D. B.

(2000). Predicting shooting scores from physical performance data. Policing: An International Journal of Police Strategies & Management, 23, 525–537. https://doi.org/10.1108/13639510010355611

Brown

M. J.

Tandy

R. D.

Wulf

Young

J. C.

(2013). The effect of acute exercise on pistol shooting performance of police officers. Motor Control, 17, 273–282.

Carr

B. G.

Nance

M. L.

Branas

C. C.

Wolff

C. S.

Kallan

M. J.

Myers

S. R.

Wiebe

D. J.

(2012). Unintentional firearm death across the urban-rural landscape in the United States. Journal of Trauma and Acute Care Surgery, 73, 1006–1010. https://doi.org/10.1097/TA.0b013e318265d10a

Cole

M. A.

Brown

M. D.

(2000). Response of the human triceps surae muscle to electrical stimulation during varying levels of blood flow restriction. European Journal of Applied Physiology, 82, 39–44. https://doi.org/10.1007/s004210050649

Degens

Sanchez Horneros

J. M.

Hopman

M. T. E.

(2006). Acute hypoxia limits endurance but does not affect muscle contractile properties. Muscle & Nerve, 33, 532–537. https://doi.org/10.1002/mus.20485

Deutscher Schützenbund e. V. (2017). Luftpistole 10m [Air pistol 10m]. Retrieved from http://www.dsb.de/sport/disziplinen/pistole/luftpistole_10m/

Deutsches Institut für Normung e. V. (2009). Augenoptik – Sehschärfeprüfung – Normsehzeichen und klinische Sehzeichen und ihre Darbietung (DIN EN ISO 8596)[Ophthalmic optics – Visual acuity testing – Standard and clinical optotypes and their presentation (ISO 8596:2009)]. Berlin, Germany: Beuth Verlag.

Deutsches Institut für Normung e. V. (2010). Teil 1: Wesentliche Maße des menschlichen Körpers für die technische Gestaltung. Körpermaßdefinitionen und – messpunkte (DIN EN ISO 7250) [Basic human body measurements for technological design – Part 1: Body measurement definitions and landmarks (ISO 7250-1:2008)]. Berlin, Germany: Beuth Verlag.

10.

Enoka

R. M.

Duchateau

(2008). Muscle fatigue: What, why and how it influences muscle function. Journal of Physiology, 586, 11–23. https://doi.org/10.1113/jphysiol.2007.139477

11.

Eßfeld

Rüther

Wunderlich

Sievert

(2007). Entwicklung einsatznaher Leistungstests und Prüfverfahren (Abschlussbericht zum Verbundprojekt M/SAB1/3/A011) [Development of operational performance tests and test methods (final report)]. Bonn, Germany: Streitkräfteamt, Abt. III, Fachinformationszentrum der Bundeswehr.

12.

Federal Ministry of Defence. (2017). A2-222/0-0-4740: Schießen mit der Pistole P8 [Military regulation: Pistol shooting]. Bonn, Germany: Author.

13.

Frykman

P. N.

Merullo

D. J.

Banderet

L. E.

Gregorczyk

Hasselquist

(2012). Marksmanship deficits caused by an exhaustive whole-body lifting task with and without torso-borne loads. Journal of Strength and Conditioning Research, 26(Suppl. 2), S30–6. https://doi.org/10.1519/JSC.0b013e31825cedfa

14.

Goonetilleke

R. S.

Hoffmann

E. R.

Lau

W. C.

(2009). Pistol shooting accuracy as dependent on experience, eyes being opened and available viewing time. Applied Ergonomics, 40, 500–508. https://doi.org/10.1016/j.apergo.2008.09.005

15.

Heim

Schmidtbleicher

Niebergall

(2006). The risk of involuntary firearms discharge. Human Factors, 48, 413–421. https://doi.org/10.1518/001872006778606813

16.

Jaworski

R. L.

Jensen

Niederberger

Congalton

Kelly

K. R.

(2015). Changes in combat task performance under increasing loads in active duty Marines. Military Medicine, 180(Suppl. 3), 179–186. https://doi.org/10.7205/MILMED-D-14-00432

17.

Karabulut

Cramer

J. T.

Abe

Sato

Bemben

M. G.

(2010). Neuromuscular fatigue following low-intensity dynamic exercise with externally applied vascular restriction. Journal of Electromyography and Kinesiology, 20, 440–447. https://doi.org/10.1016/j.jelekin.2009.06.005

18.

Knapik

J. J.

Reynolds

Staab

Vogel

J. A.

Bahrke

M. S.

O’Connor

(1991). Soldier performance and mood states following a strenuous road march. Military Medicine, 156, 197–200.

19.

Lopez

Bötel

(2017). Gelebte Normalität: Frauen in der Bundeswehr [Living normality: Woman in the German Armed Forces]. Retrieved from http://bit.ly/2uN3NaL

20.

Mon

Zakynthinaki

M. S.

Cordente

C. A.

Antón

A. J. M.

Rodríguez

B. R.

Jiménez

D. L.

(2015). Finger flexor force influences performance in senior male air pistol Olympic shooting. PloS One, 10(6), e0129862. https://doi.org/10.1371/journal.pone.0129862

21.

Mononen

Konttinen

Viitasalo

Era

(2007). Relationships between postural balance, rifle stability and shooting accuracy among novice rifle shooters. Scandinavian Journal of Medicine and Science in Sports, 17, 180–185. https://doi.org/10.1111/j.1600-0838.2006.00549.x

22.

Nakada

Demura

Yamaji

Minami

Kitabayashi

Nagasawa

(2004). Relationships between force curves and muscle oxygenation kinetics during repeated handgrip. Journal of Physiological Anthropology and Applied Human Science, 23, 191–196. https://doi.org/10.2114/jpa.23.191

23.

Nindl

B. C.

Jones

B. H.

van Arsdale

S. J.

Kelly

Kraemer

W. J.

(2016). Operational physical performance and fitness in military women: Physiological, musculoskeletal injury, and optimized physical training considerations for successfully integrating women into combat-centric military occupations. Military Medicine, 181(Suppl. 1), 50–62. https://doi.org/10.7205/MILMED-D-15-00382

24.

Oda

Kida

(2001). Neuromuscular fatigue during maximal concurrent hand grip and elbow flexion or extension. Journal of Electromyography and Kinesiology, 11, 281–289. https://doi.org/10.1016/S1050-6411(01)00004-9

25.

Radwin

R. G.

(1993). Pistol grip power tool handle and trigger size effects on grip exertions and operator preference. Human Factors, 35, 551–569. https://doi.org/10.1177/001872089303500311

26.

Orr

Pope

Stierli

Hinton

(2017). Grip strength and its relationship to police recruit task performance and injury risk. A retrospective cohort study. International Journal of Environmental Research and Public Health, 14(8), 1–11. https://doi.org/10.3390/ijerph14080941

27.

Potvin

J. R.

(2012). Predicting maximum acceptable efforts for repetitive tasks: An equation based on duty cycle. Human Factors, 54, 175–188.

28.

Rayson

M. P.

Bell

D. G.

Holliman

D. E.

Llewellyn

Nevola

V. R.

Bell

R. L.

(1994). Physical selection standards for the British Army, Phases 1 and 2 (Report No. 94R036). Farnborough, UK: Army Personnel Research Establishment.

29.

Rohde

Erley

O. M.

Rüther

Wunderlich

Leyk

(2007). Leistungsanforderungen bei typischen soldatischen Einsatzbelastungen [Performance requirements for soldiers in mission]. Wehrmedizinische Monatsschrift, 51, 138–142.

30.

Rohmert

(1960). Ermittlung von Erholpausen für statische Arbeit des Mensehen [Determination of rest periods for static work]. Internationale Zeitschrift Fur Angewandte Physiologie, Einschliesslich Arbeitsphysiologie, 18, 123–164.

31.

Rüther

Witzki

Rohde

Gorges

Krapick

Harbaum

. . . Leyk

(2015). Muskelkraft als begrenzender Faktor militärischer Tätigkeiten und Belastbarkeit von Soldatinnen [Muscular strength as a limiting factor in military activities and the resilience of female soldiers]. Deutsche Zeitschrift Für Sportmedizin, 66, 193.

32.

Savage-Knepshield

P. A.

Thomas

Schweitzer

Kozycki

Hullinger

(2016). Designing military systems for women in combat. Military Medicine, 181(Suppl. 1), 44–49. https://doi.org/10.7205/MILMED-D-15-00203

33.

Sharp

M. A.

Patton

J. F.

Vogel

J. A.

(1998). A database of physically demanding tasks performed by U.S. Army soldiers. Frederick, MD: U.S. Army Medical Research and Materiel Command.

34.

Sinauer

Annest

J. L.

Mercy

J. A.

(1996). Unintentional, nonfatal firearm-related injuries. A preventable public health burden. Journal of the American Medical Association, 275, 1740–1743.

35.

Strasser

Kluth

Keller

(2004). A computer-based system for the use of electromyographic methods for the measurement of physiological costs associated with operating hand-held tools and computer input devices. Occupational Ergonomics, 4, 73–87.

36.

Swain

D. P.

Ringleb

S. I.

Naik

D. N.

Butowicz

C. M.

(2011). Effect of training with and without a load on military fitness tests and marksmanship. Journal of Strength and Conditioning Research, 25, 1857–1865. https://doi.org/10.1519/JSC.0b013e318220dbcf

37.

Tachi

Kouzaki

Kanehisa

Fukunaga

(2004). The influence of circulatory difference on muscle oxygenation and fatigue during intermittent static dorsiflexion. European Journal of Applied Physiology, 91, 682–688. https://doi.org/10.1007/s00421-003-1024-y

38.

Tharion

W. J.

Hoyt

R. W.

Marlowe

B. E.

Cymerman

(1992). Effects of high altitude and exercise on marksmanship. Aviation, Space and Environmental Medicine, 63, 114–117.

39.

Tharion

W. J.

Rice

Sharp

M. A.

Marlowe

E. B.

(1993). The effects of litter carrying on rifle shooting. Military Medicine, 158, 566–570.

40.

Vigouroux

Quaine

(2006). Fingertip force and electromyography of finger flexor muscles during a prolonged intermittent exercise in elite climbers and sedentary individuals. Journal of Sports Sciences, 24, 181–186. https://doi.org/10.1080/02640410500127785

Index Finger Muscle Fatigue and Pistol Firing Failure

Abstract

Objective:

Background:

Method:

Results:

Conclusion:

Application:

Keywords

Get full access to this article

References