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Currently accepted at: JMIR mHealth and uHealth

Date Submitted: May 7, 2019
Open Peer Review Period: May 10, 2019 - Jul 5, 2019
Date Accepted: Jul 19, 2019
(closed for review but you can still tweet)

This paper has been accepted and is currently in production.

It will appear shortly on 10.2196/14641

The final accepted version (not copyedited yet) is in this tab.

Development of a Smartphone App for Measuring Striking Response Time in Combat Sports: A Cross-Sectional Validation Study

  • Victor Coswig; 
  • Jader Sant' Ana; 
  • Maicon Nascimento Coelho; 
  • Antonio Renato Pereira Moro; 
  • Fernando Diefenthaeler; 



The TReaction app purposes to determine strike response time with a low cost and easy application in combat sports. However, there is a need to verify the validity and accuracy of the response time obtained by the TReaction app.


To test the validity and reliability of the TReaction app in measuring the motor response time in combat sports.


Two athletes performed 59 strikes to assess the response time from visual stimulus using the TReaction app simultaneously with a high speed camera. Accuracy of the measure was verified using a simulator programmed to discharge visual stimuli and obtain the response time. Person correlation, Student t test for dependent samples, and the Bland-Altman analysis were established. The accuracy was verified by the intraclass correlation coefficient (ICC). The Effect size (g) and the typical error of measurement (TEM) were calculated. The significance level was set at p<0.05.


No significant difference (p=0.556) was found between both systems. The methods presented a very strong correlation (r=0.993). A magnitude of the differences was trivial (g<0.25) and the TEM was 1.4%. These findings indicate the accuracy of the measures of changing computer screen and the smartphone flash to determine the beginning of the task, as well as the response time.


Thus, our findings suggest that the TReaction app is valid to evaluate the response time in combat sports athletes.


Please cite as:

Coswig V, Sant' Ana J, Coelho MN, Pereira Moro AR, Diefenthaeler F

Development of a Smartphone App for Measuring Striking Response Time in Combat Sports: A Cross-Sectional Validation Study

JMIR mHealth and uHealth. (forthcoming/in press)

DOI: 10.2196/14641


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