• Accelerometery and heart rate responses of professional fast-medium bowlers in one-day and multi-day cricket

      Johnstone, James A.; Hughes, Gerwyn T.G.; Mitchell, Andrew C.S.; Ford, Paul A.; Watson, Tim; Duffield, Rob; Gordon, Dan; Roberts, Justin D.; Garrett, Andrew T.; Anglia Ruskin University; et al. (JOURNAL SPORTS SCIENCE & MEDICINE, 2017-08-08)
      The physical demands of fast-medium bowling are increasingly being recognised, yet comparative exploration of the differing demands between competitive formats (i.e. one-day [OD] versus multi-day [MD] matches) remain minimal. The aim of this study was to describe in-match physiological profiles of professional fast-medium bowlers from England across different versions of competitive matches using a multivariable wearable monitoring device. Seven professional cricket fast-medium bowlers wore the Bioharness (TM) monitoring device during matches, over three seasons (>80 hours in-match). Heart Rate (HR) and Acceleromety (ACC) was compared across match types (OD, MD) and different in-match activity states (Bowling, Between over bowling, Fielding). Peak acceleration during OD bowling was significantly higher in comparison to MD cricket ([OD vs. MD] 234.1 +/- 57.9 vs 226.6 +/- 32.9 ct.episode(-1), p < 0.05, ES = 0.11-0.30). Data for ACC were also higher during OD than MD fielding activities (p < 0.01, ES = 0.11-.30). OD bowling stimulated higher mean HR responses (143 +/- 14 vs 137 +/- 16 beats.min(-1), p < 0.05, ES = 0.21) when compared to MD matches. This increase in OD cricket was evident for both between over (129 +/- 9 vs 120 +/- 13 beats.min(-1), p < 0.01, ES = 0.11-0.50) and during fielding (115 +/- 12 vs 106 +/- 12 beats.min(-1), p < 0.01, ES = 0.36) activity. The increased HR and ACC evident in OD matches suggest greater acute physical loads than MD formats. Therefore, use of wearable technology and the findings provided give a valuable appreciation of the differences in match loads, and thus required physiological preparation and recovery in fast-medium bowlers.
    • Field based reliability and validity of the Bioharness (TM) multivariable monitoring device

      Johnstone, James A.; Ford, Paul A.; Hughes, Gerwyn T.G.; Watson, Tim; Mitchell, Andrew C.S.; Garrett, Andrew T.; University of Hertfordshire; University of Hull; British Olympic Association (JOURNAL SPORTS SCIENCE & MEDICINE, 2012-12-01)
      The Bioharness (TM) device is designed for monitoring physiological variables in free-living situations but has only been proven to be reliable and valid in a laboratory environment. Therefore, this study aimed to determine the reliability and validity of the Bioharness (TM) using a field based protocol. Twenty healthy males participated. Heart rate (HR), breathing frequency (BF) and accelerometry (ACC) were assessed by simultaneous measurement of two Bioharness (TM) devices and a test-retest of a discontinuous incremental walk-jog-run protocol (4 -11 km.h(-1)) completed in a sports hall. Adopted precision of measurement devices were; HR: Polar T31 (Polar Electro), BF: Spirometer (Cortex Metalyser), ACC: Oxygen expenditure (Cortex Metalyser). For all data, precision of measurement reported good relationships (r = 0.61 to 0.67, p < 0.01) and large Limits of Agreement for HR (>79.2 b.min(-1)) and BF (>54.7 br.min(-1)). ACC presented excellent precision (r = 0.94, p < 0.01). Results for HR (r = similar to 0.91, p < 0.01: CV < 7.6) and ACC (r > 0.97, p < 0.01; CV <14.7) suggested these variables are reliable. BF presented more variable data (r = 0.46-0.61, p < 0.01; CV < 23.7). As velocity of movement increased (> 8 km.h(-1)) data became more erroneous. A data cleaning protocol removed gross errors in the data analysis and subsequent reliability and validity statistics improved across all variables. In conclusion, the Bioharness (TM) HR and ACC variables have demonstrated reliability and validity in a field setting, though data collected at higher velocities should be treated with caution. Measuring human physiological responses in a field based environment allows for more ecologically valid data to be collected and devices such as the Bioharness (TM) could be used by exercise professionals to begin to further investigate this area.