Aim of this research is to compare novel 3D printed cycling saddle with the bestselling saddles from two major cycling manufacturers in terms of effects on penile blood gasses and update these findings on current style of racing cycling saddles.
The aim of this research is to investigate whether Posedla's 3D printed and custom-made prototype bicycle saddle Joyseat (Posedla s.r.o., Varnsdorf, Czech Republic) provide a benefit in terms of increased penile blood flow compared to the best-selling saddles from two major bicycle manufacturers. The method chosen to measure blood flow, which is commonly used in studies of this type, is referred to as transcutaneus blood gas monitoring. Measurement of TcPO2 and TcPCO2 in cyclists will be performed while riding on a cycling trainer using Radiometer TCM5 Flex (Radiometer Medical ApS, Brønshøj, Denmark) and a tc 84 electrode placed on the glans penis. Prior to the actual penile blood flow measurements, the sensitivity level of the n. pudendus (n. dorsalis penis) will be verified using biothesiometer (Bio Medical Instruments Co., Newbury, Ohio, USA), which is again commonly used in studies of this type. The pressure of the riders contact surfaces on the saddle will be evaluated with Velometrik SmartCover BT pressure mat (Velometrik GmbH, Neukieritzsch, Germany). The Wahoo KICKR Bike (Wahoo Fitness, LLC., Atlanta, Georgia, United States of America) will be used in the study, which, in addition to the possibility of individual seating adjustment, also allows to record the cyclists power and heart rate using a chest strap. The cyclists position on the bike will be measured and evaluated by infrared sensors and Retül technology (Specialized Bicycle Components, Inc., Morgan Hill, California, USA). The test will be performed using the described instrumentation in the Applied Kinesiology Laboratory at Charles University in Prague, Faculty of Physical Education and Sports and will involve riding 3x 10 minutes with 5 minutes rest in between intervals on the cycle trainer at 65-85% of the cyclists maximum individual heart rate during one visit. All measurement methods and devices are non-invasive and painless. The choice of instruments was based on their use in previously published studies of similar type and on their quality, i.e., the parameters of validity, reliability, sensitivity, specificity and availability.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Biothesiometry using Biothesiometer (Bio Medical Instrument Co, Ohio, United States of America), placed on glans penis and second finger of nondominant hand.
Penile oxygen pressure using TCM5 Flex and tc84 electrode (Radiometer Medical ApS, Brønshøj, Denmark) placed on glans penis.
Riding a static bike Wahoo Bike (Wahoo Fitness LLC, Atlanta, Georgia, United States of America) for 3x 10 minutes in Zone 3 (Andy Coggan methodology) calculated from each individual subjects self reported Functional Threshold Power.
Charles University
Prague, Czechia
pO2_change_point
Parameter pO2\_change\_point is the time from start of TcPO₂ measurement to the identified change point, determined within the 50-400 s interval as the transition between the fitted initial linear trend and the subsequent linear trend in TcPO₂
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_change_point
Parameter pCO2\_change\_point is the time from start of TcPCO₂ measurement to the identified change point, determined within the 200-550 s interval as the transition between the fitted initial linear trend and the subsequent linear trend in TcPCO₂
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_start
The value of the fitted trend at time 0 in TcPO₂ measurement.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_decline
The slope of the fitted trend of decline in TcPO₂ after initial 20s.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_end
The slope of the second fitted trend after pO2\_change\_point in TcPO₂ measurement.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
14
Setting standardized posture of the rider on the bike using Retül technology (Retül, Specialized Bicycle Components Inc., Boulder, Colorado, United States of America)
Measuring heart rate using Wahoo TICKR chest strap (Wahoo Fitness LLC, Atlanta, Georgia, United States of America)
Saddle pressure measurement, mean and max saddle pressure, saddle pressure distribution. (Velometrik GmbH, Neukieritzsch, Germany).
pO2_part1
The average value of TcPO₂ measurements in the first 20 s segment.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_part2
The average value of TcPO₂ measurements for the second segment, from 21 s to the trend pO2\_change\_point.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_part3
The average value of TcPO₂ measurements for the third segment after pO2\_change\_point.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_mean
The average of all TcPO₂ measurements in one interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_median
The median of all TcPO₂ measurements in one interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_start
The value of the fitted trend at time 0 in TcPCO₂ measurement.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_incline
The slope of the fitted trend of increase in TcPCO₂ in the first segment before pCO2\_change\_point
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_end
The slope of the fitted trend in TcPCO₂ in the second segment after pCO2\_change\_point.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_part1
The average value of TcPCO₂ measurements in the first segment before pCO2\_change\_point.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_part2
The average value of TcPCO₂ measurements in the second segment after pCO2\_change\_point.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_mean
The average of all TcPCO₂ measurements in one interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_median
The median of all TcPCO₂ measurements in one interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
logratio_11_8
The logarithmic value of the ratio of the load on the front and rear parts of the saddle, where the saddle is divided in a ratio of 11:8 longitudinally.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
PERI
Pressure value in the predefined perineal area with an area of 44 cm² in front of the ischial tuberosity maxima.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
modPSRG/F
Vibrotactile thresholds were measured at the volar distal phalanx of the non-dominant hand and midline of the glans penis. The probe was placed perpendicular without additional pressure. Voltage was gradually increased until the first sensation was reported, then increased further and slowly decreased until sensation was lost. Upper and lower thresholds were recorded three times per site, averaged, and used to calculate the modified Penile Sensitivity Ratio Glans/Finger via the following formula. Average of the three glans upper+lower threshold values divided by the average of the three finger upper+lower threshold values.
Time frame: A baseline testing at the beginning of the testing protocol lasting around 5 minutes.
CVdrift
The percentage of cardiovascular drift calculated as a ratio between average Power and average Heart Rate between the first and second part of the 10-minute interval. ((P1/HR1) - (P2/HR2))/(P1/HR1) \* 100 where: P1 - Average Power from first half part of the workout P2 - Average Power from second half part of the workout HR1 - Average Heart Rate from first half part of the workout HR2 - Average Heart Rate from second half part of the workout
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
Bike Fit parameters
Bike Fit values as recorded by Retül V7 System. KOPS - Knee Over Pedal Spindle - The fore/aft offset of the knee marker relative to the pedal spindle at 3 o'clock in the pedal stroke (90° in the downstroke) MKF - Maximum Knee Flexion - Maximum flexion of the knee joint at any point in the pedal stroke defined by the line connecting hip and knee markers and the line connecting knee and ankle markers MKE - Maximum Knee Extension - Maximum extension of the knee joint at any point in the pedal stroke defined by the line connecting hip and knee markers and the line connecting knee and ankle markers SAW - Shoulder Angle to Wrist - The angle of the shoulder joint defined as the angle at intersection of the line connecting hip and shoulder markers, and the line connecting wrist and shoulder markers BA - Back Angle - The angle of the back relative to the horizon defined by the hip and shoulder marker
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_start
Mean of first 12s of TcPO₂ measurements in each 10 minute interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pO2_end
Mean of last 12s of TcPO₂ measurements in each 10 minute interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_start
Mean of first 12s of TcPCO₂ measurements in each 10 minute interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).
pCO2_end
Mean of last 12s of TcPCO₂ measurements in each 10 minute interval.
Time frame: During a single laboratory visit consisting of three 10-minute cycling intervals with three 5-minute pause time in between cycling intervals (total assessment time approximately 45 minutes).