1. Resting Heart Rate Variability in Professional Baseball Pitchers
Logan Thorp1 (Student), Kyle T. Ebersole1 (Faculty Sponsor), David J. Cornell1,
Christian Polega2, Jeff Paxson2, Josh Seligman2, Roger A. Caplinger2
1Human Performance & Sport Physiology Laboratory, Integrative Health Care & Performance - Department of Kinesiology, College of Health
Sciences, University of Wisconsin-Milwaukee,
2Milwaukee Brewers Baseball club
Subjects
Ten professional baseball pitchers from a Class A team (age=23.6±1.3 yrs,
height=188.60±3.89 cm, body weight=96.0±7.68 kg) volunteered to
participate in the current research study on resting HRV.
Procedures
A Zephyr physiological remote monitoring system was used to record a 10-
minute, continuous resting HR from each player in a supine position. In-
game HR was recorded during the entire game and HR while on the mound
pitching was averaged across all innings for a composite in-game average
HR. The data for the current study reflects the resting HR recorded in the
morning on the day that the participant pitched in a game and includes a
total of 150 games from the 2013 baseball season. Kubios Software
(University of Finland) was used to determine the RMSSD. Pitching
metrics of BF and BFPIP were determined for each game from data
supplied by the team. Bivariate Pearson correlations were used to examine
the relationship between the time-method domain of RMSSD and in-game
HR with BF, and BFPIP.
Statistical Analyses
Bivariate Pearson correlations were used to examines the relationships
between the Heart Rate Variability time-domain method of RMSSD and
in-game HR, BF, and BFPIP. Correlations for In-game Heart Rate were
also examined with BF and BFPIP.
According to the results of this study, the correlations between RMSSD and HR,
BF and BFPIP appear to be related. Pitchers who were under greater sympathetic
control at rest (i.e. lower RMSSD) faced a greater number of batters during the
game later that day. Pitchers who were under a greater parasympathetic control
(i.e. higher RMSSD) at rest faced a lower number of batters during the game that
day. Interestingly, BF was associated with a lower resting RMSSD and a higher
in-game HR. In other words, when the in-game heart rate increase, a pitcher
faces less batters. These results suggest that pitchers who have a greater range in
HR from rest to in-game, during Day-1 of measurements, may be more efficient
in pitch performance. Future investigation should examine the relative
contribution of preparation for pitching and/or psychological measures of
performance to better understand this potential performance relationship.
METHODS
RESULTSINTRODUCTION
DISCUSSION
Mean ± standard deviation results were 77.7±30.3 ms (RMSSD), 168.5±7.60
bpm for in-game HR, 18.4±3.39 BF/game, and 22.3±1.82 BFPIP. Pearson
correlations indicated strong relationships between RMSSD and in-game HR
(r=0.67), BF (r=-0.56), and BFPIP (r=-0.67). In-game HR of the subjects of
this study were also strongly correlated with BF (r=-0.84) and BFPIP
(r=-0.455). Total Pitches, Innings Pitched, and the wins and losses across the
2013 season are listed below.
Table 1. Descriptive Analysis
ABSTRACT
PURPOSE: Heart rate variability (HRV) has been suggested to
provide insight into the relative contributions of the
sympathetic and parasympathetic nervous systems on heart rate
control. No prior study has examined the relationship between
HRV and pitch performance in professional baseball pitchers.
The purpose of this research project was to examine the
relationship between the HRV measure of root mean square of
the standard deviation (RMSSD) of the R-R interval and in-
game heart rate (HR) and pitch performance metrics of total
batters faced (BF) and a new metric of BFPIP [(batters faced +
total pitches)/ innings pitched]. METHODS: Ten professional
baseball pitchers from a Class A team (age=23.6±1.3 yrs,
height=188.60±3.89 cm, body weight=96.0±7.68 kg)
volunteered to participate in the current research study. A
Zephyr physiological remote monitoring system was used to
record a 10-minute, continuous resting HR from each player in
a supine position. In-game HR was recorded during the entire
game and HR while on the mound pitching was averaged
across all innings for a composite in-game average HR. The
data for the current study reflects the resting HR recorded in the
morning on the day that the participant pitched in a game and
includes a total of 150 games from the 2013 baseball season.
Kubios Software (University of Finland) was used to determine
the RMSSD. Pitching metrics of BF and BFPIP were
determined for each game from data supplied by the team.
Pearson correlations were used to examine the relationship
between RMSSD and in-game HR with BF, and BFPIP.
RESULTS: Mean ± standard deviation results were 77.7±30.3
ms (RMSSD), 168.5±7.60 bpm for in-game HR, 18.4±3.39 BF/
game, and 22.3±1.82 BFPIP. Pearson correlations indicated
strong relationships between RMSSD and in-game HR (=0.67),
BF (r=-0.56), and BFPIP (r=-0.67). In-game HR was also
strongly correlated with BF (r=-0.8) and BFPIP (r=-0.455).
CONCLUSION: Pitchers who were under greater sympathetic
control at rest (i.e. lower RMSSD) faced a greater number of
batters during the game later that day. Interestingly, BF was
associated with a lower resting RMSSD and a higher in-game
HR. These results suggest that pitchers who have a greater
range in HR from rest to in-game may be more efficient in pitch
performance. Future investigation should examine the relative
contribution of preparation for pitching and/or psychological
measures of performance to better understand this potential
performance relationship.
ID W L
Total
Games
Average
In-Game
HR
BF/
Game
Pitches/
Game
Total
Innings
Pitched
1 5 1 11 165.4 21.1 82 54
3 7 8 24 164.4 21.5 81.4 113.19
5 0 1 3 162.2 21 83.3 15
6 4 7 25 161.2 18.3 67.4 99.66
10 2 5 16 171.5 17.1 65.9 60.77
13 2 6 21 163 21.7 77.5 100.33
14 4 7 25 174.4 17.9 67.9 98.76
15 3 4 8 164 19.9 74.0 33
16 2 6 7 174.3 12.7 41.8 21.2
17 2 5 10 185 12.7 45.9 20.7
Heart rate variability (HRV) has been suggested to provide insight into the
relative contributions of the sympathetic and parasympathetic nervous
systems on heart rate control. Root mean square of the standard deviation
(RMSSD) has been suggested to reflect the level of contribution from the
sympathetic nervous system. Baseball pitchers are a population that likely
experience a range in control of the heart rate and HRV measures may
provide insight into the relative relationship between the autonomic
nervous system and pitching performance. No prior study, however, has
examined the relationship between HRV and pitch performance in
professional baseball pitchers. The purpose of this research project was to
examine the relationship between the HRV measure RMSSD and in-game
heart rate (HR) and pitch performance metrics of total batters faced (BF)
and a new metric of BFPIP [(batters faced + total pitches)/ innings
pitched].
ACKNOWLEDGEMENT
We thank the Milwaukee Brewers Baseball club for funding this project and
the Wisconsin Timber Rattlers for supporting the data collection..