Embed Size (px)
Citation preview
Nihilvo
lentibusa
rdu
um
Effects of different local cooling Effects of different local cooling applications on the endurance capacity applications on the endurance capacity
during cyclingduring cycling
Hohenauer E.1, Clijsen R.1, Cabri J.2, Clarys P.3
1 University College Physiotherapy „Thim van der Laan“, Landquart, CH2 Center for Research in Physiotherapy, Technical University Lisbon, POR3 Department of Human Biometry and Biomechanics, Vrije Universiteit Brussel, B
Nihilvo
lentibusa
rdu
um
Introduction
Physical activity
• Core body temperature ↑• Muscle temperature ↑• Heat strain ( Hyperthermia ) • Exercise performance ↓• Heat related illnesses ↑
Duffield et al., 2003 ( Br J Sports Med )
Nihilvo
lentibusa
rdu
um
Introduction
• Disturbed thermoregulation
• Evaporation
- releases heat during exercise
• ( Pre- ) Cooling - skin temperature ↓
- counteract the negative effects of heat strain ?
Nybo et al., 2007 ( J Appl Physiol )
Nihilvo
lentibusa
rdu
um
Introduction• Menthol – alcohol solution
• High evaporation rate
• High cooling rate - surrounding area - rest of the body
• Avoid „build-up“ of heat - improve physical
performance
!? Evidence based ?!
www.energicer.co.uk
Nihilvo
lentibusa
rdu
um
Introduction
• Clijsen et al., 2008 ( ECSS, Estoril ) - 2 Energicer bands
- Swiss Olympic Guidelines, 2001 - Comfortable environmental conditions ( 23°C, 40% )
• Results - Local cooling of the upper arms by two Energicer®
bands does not enhance the endurance capacity during cycling
• Discussion - Environmental conditions too marginal? - Skin surface too small?
Nihilvo
lentibusa
rdu
um
Objective
Do different local cooling applications enhance the endurance capacity during cycling under hot and humid environmental conditions?
Nihilvo
lentibusa
rdu
um
Material & Methods
Sample:
• 7 healthy male subjects
• Mean age = 39.1 ± 9.6 yrs
• BMI = 28.2 kg.m-2
Nihilvo
lentibusa
rdu
um
Material & Methods
Sana bike 150F ( Ergosana, Bitz, GER ) • Incremental bike ergometer test• 3 min. stages ( +30W )
Stufe Zeit Watt HF Laktat Temp. BORG1 3 Min 1002 6 Min 1303 9 Min 1604 12 Min 1905 15 Min 2206 18 Min 2507 21 Min 2808 24 Min 3109 27 Min 34010 30 Min 37011 33 Min 40012 36 Min 43013 39 Min 460
2x 4x
Nihilvo
lentibusa
rdu
um
Material & Methods
• Randomised cross - over design
- 4 conditions:
No cooling With cooling vest With cooling bands With cooling vest & bands
• Environmental conditions - Temperature: 35°C ( ± 3°C ) - Humidity: 44% ( ± 5% )
Nihilvo
lentibusa
rdu
um
Material & Methods
• Vest
- saturated with 225ml
• Bands ( 7.5 x 5 x 0.5 cm )
- saturated with 25ml
Nihilvo
lentibusa
rdu
um
Measurments
• Dependent variables: - Time to exhaustion
- Heart rate
( Polar T31, Polar Inc., Kempele, FIN )
- Blood lactate
( Biosen S- line, EKF Diagnostic, Barleben, GER )
- Core temperature
( ThermoScan 6013, Braun, Kronberg, GER )
- Rated perceived exertion
( BORG scale: 6-20 )
Nihilvo
lentibusa
rdu
um
Results
Values are Means ± 1 SD
Cycle time to exhaustion
1197 1224 12081213
0
200
400
600
800
1000
1200
1400
1600
Tim
e (
se
c) No cooling
Cooling vest
Cooling bands
Cooling vest & bands
Nihilvo
lentibusa
rdu
um
Results
Values are Means ± 1 SD
Blood lactate at end of test
0
2
4
6
8
10
12
14
16
Blo
od
lac
tate
(m
mo
l.l-1
)
No cooling
Cooling vest
Cooling bands
Cooling vest & bands
Nihilvo
lentibusa
rdu
um
Results
Values are Means ± 1 SD
Core temperature
33
34
35
36
37
38
39
40
41
W100 W130 W160 W190 W220 W250 W280 W310 W340
Te
mp
era
ture
(°C
)
No cooling
Cooling vest
Cooling bands
Cooling vest & bands
XXXXXIIIIIIIIIIIIIIIIIÄÄÄÄÄÄÄWWWW
Nihilvo
lentibusa
rdu
um
Discussion
• Core temperature vs. Skin temperature• Precooling time too short• Airflow• Different test protocol
• More comfortable feeling with cooling vest - Psychological advantage?
Nihilvo
lentibusa
rdu
um
Conclusion
• Under hot and humid environmental conditions local cooling of the upper arms and/or upper body by Energicer® bands and/or vests doesn’t enhance the endurance capacity during cycling
• FUTURE RESEARCH - Airflow - Skin temperature - Sensitive test protocol
