1. Sports Coaching
Pedagogy
Downhill Running as an Eccentric
Exercise and its effect on Muscle
Strength and Damage
By Jaclyn Sweeny

2. Overview of Presentation
 Definitions of Key Terms
 Background on Downhill Running and Importance
of Study
 Review of Literature
 Practical Applications
 Further Research
 Conclusion and Summation

3. Definitions
 Downhill running is an activity whereby muscles strongly contract
eccentrically.
 Eccentric Muscle Contractions
 Occur when activated muscles are forcibly lengthened (ENOKA, R. 1996).
 Take place as a braking force working in opposition to a concentric
contraction.
 Muscle Strength
 Encompasses physiological strength, neurological strength and
mechanical strength of the muscle.
 Muscle Hypertrophy
 Increase in the cross-sectional size of a muscle due to muscle cell
growth.
 Exercise Induced Muscle Damage (EIMD)
 Involves partaking in heavy and lengthy exercise in which the muscles
are not adapted to, particularly eccentric muscle contractions.
 Delayed Onset Muscle Soreness (DOMS)
 Occurs after unaccustomed eccentric muscle action of sufficient
intensity and/or duration causes disruption of connective and/or
contractile tissue (BYRNES , CLARKSON, WHITE et al. 2008).

4. Downhill Running
 Significantly easier for metabolic and
cardiovascular systems.
 Muscles of the hip, legs and ankles, particularly
knee and hip extensors, must work hard in
downhill running.
 Studies involving downhill running and muscle
strength or damage are very important in
assessing and implemented eccentric muscle
contracting exercises into an athletes’ training
regime.
 You Tube Video
 http://www.youtube.com/watch?v=mFxs7ESuxWc

5. Literature Review 1- Changes in Power Assessed by
the Windgate Anaerobic Test Following Downhill
Running.
 Purpose
 The effect of eccentric induced muscle damage on
power is a key performance variable in a variety of
sporting contexts.
 Aim
 Examine changes in anaerobic power (through a 30
second Windgate test), isometric strength of knee
extensors and flexors, muscle soreness and plasma
Creatine Kinase (CK) activity following downhill
running (NOTTLE , NASAKA. 2007).
 Method
 8 men ran a downhill running protocol of a -7%
gradient for 40 minutes before testing parameters

6. •
Results

7. Literature Review 2 –Leukocytes, Cytokines, Growth Factors
and Hormones in Human Skeletal Muscle and Blood After
Uphill or Downhill Running
 Purpose
 investigate inflammatory processes in human
skeletal muscle and epimysium after acute physical
exercise with large eccentric contractions (MALM,
SJODIN, SJOBERG et al. 2004.).
 Method
 25 male and 3 female subjects were randomly
assigned downhill running protocols of -4 degree or
-8 degree gradient, an uphill running protocol of 4
degree gradient or control group.
 The subjects performed the run for 45mins.
 Muscle biopsy, knee extensor muscles, muscle
soreness , immunohistochemistry, image analysis,
blood samples, flow cytometry and serum
hormones and proteins.

8.  Results
 Indicated only the subjects who undertook the
downhill running protocol experienced DOMS as
well as a decrease in muscle function and an
increase in creatine Kinase activity.

9. Literature Review 3- Changes in Running Economy
Following Downhill Running.
 Purpose
 to establish any changes in running economy after a
30minute downhill run
 Method
 10 male soccer players.
 30minute downhill run and subsequent level runs.
 Parameters included oxygen consumption,
respiratory exchanged ratio, heat rate, ratings of
perceived exhaustion, blood lactate, stride length,
stride frequency and range of motion of ankle, knee
and hip.

10.  Results

11. Practical Applications
 Utilisation in training programs.
 Understanding adaptive mechanisms of muscles.
 Eccentric Exercises and the advantages for
training.
 EIMD and DOMS - how detrimentally effect the
muscles and for what period of time (alter training
and recovery around these findings).
 Benefits of exercise and physical activity on
sufferers of inflammatory muscle diseases.

12. Further Research
 Specific Downhill running protocols and training
sessions to optimise muscle power and strength
gains.
 Research into the benefits and detriments of
downhill running on various sports to ensure that
the utilisation of eccentric training is enhancing
performance sports specifically.

13. Conclusion and Summation
 Downhill running is a very prominent eccentric
exercise used by many coaches and athletes as
a part of their training regime.
 Through the literature evaluated it can be
concluded that eccentric exercise such as
downhill running decreases peak and average
power, strength, increases creatine Kinase
activity and is associated with EIMD and DOMS.

14. Reference List
Journal Articles
 NOTTLE , NASAKA. 2007. Changes in Power Assessed by the Windgate Anaerobic Test Following Downhill Running. Journal of
Strength and Conditioning Research, 21, 145-150.
 MALM, SJODIN, SJOBERG et al. 2004. Leukocytes, Cytokines, Growth Factors and Hormones in Human Skeletal Muscle and Blood
after Uphill or Downhill Running. Journal of Physiology, 3, 983-1000.
 CHEN, NOSAKA, TU. 2007. Changes in Running Economy Following Downhill Running. Journal of Sports Sciences, 25, 55-63.
 ENOKA, R. 1996. Eccentric Contractions Require Unique Activation Strategies by the Nervous System. Journal of Applied
Physiology, 81, 2339-2346.
 BYRNES , CLARKSON, WHITE et al. 2008. Delayed onset muscle soreness following repeated bouts of downhill running. Journal of
Applied Physiology, 1.
 UNIVERSITY, E. C. 1991. Acute inflammation: the underlying mechanism in delayed onset muscle soreness? . Medicine and Science
in Sport and Exercise, 23.
 CLARKSON, HUBEL. 2002. Exercise Induced Muscle Damage in Humans. Journal of Physiology Medical Rehabilitation, 81, 52-69.
You tube
 YOU TUBE,. 2011. Downhill Trail Running. In: ENDUROEXPLORER (ed.). Date Viewed 03/04/2012
http://www.youtube.com/watch?v=mFxs7ESuxWc
Images
 Image 1
 http://www.usatriathlon.org/about-multisport/multisport-zone/multisport-
lab/articles/~/media/7daee9855b174a9ba6dfcff15492c9d5.ashx
 Image 2
 http://static.flickr.com/53/131607152_3a01c5276f_m.jpg