1. No category

Gender differences in training adaptations
in tendon and skeletal muscle
Ass.Prof Mette Hansen
AA R H U S U N I V E R S I T Y
Section of Sports Science,
Department of Public Health
Gender differences in the
musculoskeletal system
Muscle mass/kg
Muscle power
Bone mass & density
Osteoporosis½½½
Tendon size/kg
M>W
M>W
M>W
M<W
M>W
Musculoskeletal flexibility ½M < W
Joint laxity
M<W
Skeletal muscle – Estrogen receptors
Wiik et al 2003, 2005
West et al, J appl Physiol, 2012
Majority of studies have shown NO gender difference
in basal muscle protein turnover
(Dreyer HC et al, Acta Physiol, 2010; Fujita S, et al, Am J Physiol Endocrinol Metab, 2007; Jahn LA et
al, J Clin Endocrinol Metab, 1999; Parise G et al, J Appl Physiol, 2001)
Myofibrillar protein synthesis rate
Young women and men
1 hr 1-legged kicking
exercise (similar relativ load)
Mean±SEM
Muscle connective tissue
No significant gender difference in muscle
collagen synthesis in young subjects
Miller BF, et al, Am J Physiol Endocrinol Metab, 2006
Estrogen replacement therapy enhance the
response to exercise in skeletal muscle
Myofibrillar protein synthesis
 Exercise - Rest (% h-1)
#
*
0.025
0.020
0.015
0.010
0.005
0.000
Postmenopausal
women
-0.005
-0.010
-0.015
Control
Estrogen
 Exercise - Rest (% h-1)
Muscle collagen synthesis
0.020
*
0.015
0.010
0.005
0.000
Control
Hansen M, et al, J Gerontology, 2012
Estrogen
10*10 rep (10 RM)
10 weeks strength training
Use of oral contraceptives
- effect on adaptation to resistance
exercise training in skeletal muscle
Training * OC
interaction
p=0.04
Training * OC
interaction
p=0.066
Increase in Muscle CSA
Non- oral contraceptive users
8 ± 1%
Oral contraceptive users (30 µg Ethinyl estradiol) 13 ± 2%
Oral contraceptive users (20 µg Ethinyl estradiol) 9 ± 1%
P=0.01
Hansen et al, New unpublised results
Conclusion 1/2
No gender difference in relative muscle growth, but
- Testosteron may be important for the adaptation
in men
- Estrogen may be important for the adaptation in
women
(adults)
Gender differences in ligament
and tendon adaptation to
training
Anterior Cruciate Ligament (ACL) rupture
2-8  risk in ♀ vs ♂
Receptors for estrogen
are identified in the
human ACL & tendons
(Faryniarz et al, 2006, Liu et al, 1996, Sciore et
al, 1998)
(Huston et al, 2000, Hewett et al., 2006)
Stable isotope technique
Tendon Biopsies (patellar tendon)
[13C] proline (flooding dose)
Patella tendon collagen
Lower tendon synthesis in
women compared to men
Tendon collagen synthesis
0.07
Rest
0.06
#
(% h)
0.05
0.04
# Women vs Men
0.03
0.02
0.01
0.00
Women
Miller BF et al, 2006
Men
Patella tendon collagen
Lower tendon synthesis in
women compared to men
0.07
0.06
Tendon collagen synthesis
#*
Rest
72 h post exercise
#
(% h)
0.05
0.04
# Women vs Men
0.03
* Exercise vs rest
0.02
0.01
0.00
Women
Miller et al, 2006
Men
Female Tendon fascicles ruptures before male fascicles
Haraldsson B et al, 2006
Female fascicles rupture at a lower load than male fascicles
Haraldsson, B. et al, 2009
Tendon dry mass per mg tendon w.w.:
LeMoine JK, et al 2009
Type III collagen mRNA: Women > Men
Sullivan et al 2009
Women < Men
Female fascicles rupture at a lower load than male fascicles
Haraldsson, B. et al, 2009
Tendon dry mass per mg tendon w.w.:
LeMoine JK, et al 2009
Type III collagen mRNA: Women > Men
Sullivan et al 2009
Tendon relativ stiffness during
MVIC & Ultrasound recording
Women < Men
Onambele et al. 2007
Women < Men
Patellar tendon cross-sectional area (CSA)
•
** P<.001 compared to trained men
♀
♀
Magnusson SP et al, 2007, Westh E et al, 2008
♂
♂
Gender differences in ligament and tendon adaptation to training
Caused by estrogen?
Tendon composition & biomechanical properties
Hansen M, et al,J.Appl.Physiol, 2009, 106(4), pp 1385,
Control
Estrogen-users
Control (n=9)
Relative stiffness (Young Modulus)
Control > Estrogen
ERT-users (n=7)
% fibrils, dia 0-60 nm
27 ± 2
24 ± 2
% fibrils, dia 61-90 nm
30 ± 2
50 ± 8 (P<0.05)
% fibrils, dia > 90 nm
43 ± 2
26 ± 8 (P=0.10)
Pregnancy and joint laxity
Charlton et al, 2001
Estradiol
Decrease in
knee laxity in
38/40 women
Week 30
5-7 weeks post
Estrogen  Reduced relativ tendon stiffness: beneficial?
High serum estrogen associated with low
tendon stiffness in female handball players
Hansen et al, in preparation
ACL injuries: Higher risk in the
preovulatory phase of the menstrual cycle
where the estrogen level is high
Adachi N, Arch Orthop Trauma Surg, 2008
Gender differences in ligament and tendon adaptation to training
Conclusion 2/2
Cross-sectional data indicate gender difference in:
• Tendon structure (dry weight mass, type III collagen etc)
• Fascicle strength (women<men)
• Tendon biomechanical properties (tendon stiffness women<men)
• Akut response to exercise in tendon collagen synthesis (women<men)
• Tendon adaptation to training (women<men)
A high level of circulating estradiol is associated with:
- A higher tendon collagen synthesis rate
- Reduced tendon stiffness
- A higher risk of ACL injuries
Acknowlegdements
Participants in the studies
Collaborators:
At Institute of Sports Medicine: Michael Kjær, Henning Langberg, Jesper L
Andersen, Christian Couppé, Christina SE Hansen, Dorthe Skovgaard, Per
Aagaard, S. Peter Magnusson, Tina Louise Nielsen, Sara Søkilde, Phillip
Hansen, Ida Carøe, Susanne G. Petersen, Satu Koskinen, Eva Westh, Bjarki
Haraldsson, Ann-Marie Sedstrøm
Jytte O. Larsen & Klaus Qvortrup (Copenhagen University, Denmark)
Per Aargard (Southern Denmark University, Odense, Denmark
Ben Miller, Todd Trappe (USA)
Michael Rennie (UK)
Jan Frystyk, Allan Flyvbjerg (Aarhus, Denmark)
Vuokko Kovanen (Finland)
Finansial support:
The Danish National Research Foundation, the Ministry of Culture Committee on
Sports Research, The Copenhagen University Hospital Foundation, The Danish
Rheumatism Association, The MedicalResearch Council of Denmark Danish Health
Science Research Board, the Lundbeck Foundation, the Eva and Henry Frænkels
Memorial Foundation and Clinical Institute at Aarhus University Hospital, EU 7th
framework grant “Myoage”, Nordea Foundation (Healthy Ageing grant), the A.P.
Møller Foundation for the Advancement of Medical Science