Lecture 13 - P&FWB Flashcards
Lecture 13:
What are 2 key ways that cancer harms one’s physical function?
1.) Loss of muscle (cardiac & skeletal) *common
2.) Factors causing muscle wasting
Lecture 13:
What are 2 factors that contribute to muscle wasting in cancer patients?
Cytokines & Fatty acid-derived eicosanoids
Lecture 13:
What are Fatty acid-derived eicosanoids?
Signalling molecules in the body that are tied tightly to inflammation
Lecture 14:
What are 2 types of muscle wasting that contribute to physical function harms?
Cachexia - muscle wasting that can lead to death & greatly effects cardiac muscles
Atrophy - loss of muscle mass (typically due to injury/underutilization)
Lecture 13:
What are 2 reasons why cancer patients lose lean muscle mass?
1.) Decline in protein synthesis
2.) Enhanced protein catabolism
Lecture 13:
When discussing loss of muscle mass in cancer patients, why does a decline in protein synthesis occur?
- physical inactivity (deconditioning)
- reduction in supply of amino acids in protein production
Lecture 13:
When discussing loss of muscle mass in cancer patients, why does enhanced protein catabolism occur?
(Aka protein degradation)
Protein degradation occurs form increased expression of components in the ubiquities-proteasome proteolytic pathway
Lecture 13:
How does loss of lean muscle mass affect muscle?
- reduced muscle & muscle fibre cross-sectional area
- loss of muscle extensibility
- decrease in proteins needed for metabolism
Lecture 13:
What are some things that those with Reduced protein synthesis & enhanced muscle degradation experience?
- muscle weakness
- decreased functional work capacity
- decreased flexibility
- reduced mobility
- diminished quality of life
Lecture 13:
When does a decrease in muscle endurance occur in healthy populations vs cancer?
Decreases in muscle endurance occurs after 2 weeks of inactivity as well as aging in healthy populations & is potentially worse in cancer populations
Lecture 13:
What did Ringholm et a; study in 2011?
12 health young men that were put on bed rest for 7days to test muscle mass changes from inactivity
Lecture 13:
In Ringholm’s 2011 7-day study of 12 healthy young men, how were muscle mass changes measured?
Knee extensor exercise was done before & after bed rest
Lecture 13:
In Ringholm’s 2011 7-day study of 12 healthy young men, what were the resulting changes in muscle mass?
7-day bedrest caused:
- reduced skeletal muscle metabolic capability
- reduced exercise induced adaptive gene responses (interferes with skeletal muscle’s ability to adapt)
Lecture 13:
In LaStayo et al’s 2011 study of older cancer survivors & eccentric exercises, who were the participants?
40 long-term cancer survivors with average age of 74yrs
Lecture 13:
In LaStayo et al’s 2011 study of older cancer survivors & eccentric exercises, what were the 2 groups participants were split into?
1.) RENEW group - performed eccentrically-induced work (low exertion used to produce high muscle workloads & positive changes in muscle/mobility)
2.) CONTROL group
Lecture 13:
In LaStayo et al’s 2011 study of older cancer survivors & eccentric exercises, how long did the intervention/study last?
12 weeks
Lecture 13:
In LaStayo et al’s 2011 study of older cancer survivors & eccentric exercises, what did the RENEW group do for the 12 weeks?
- recumbent eccentric stepper (pedals go back)
- resist motion by pushing on pedals
- 3x/week in 3-5min sessions to start and then 16-20mins for the last 8 weeks
- RPE was “somewhat hard”
Lecture 13:
What were the results of LaStayo et al’s 2011 study of older cancer survivors & eccentric exercises?
- increases seen in quads lean tissue and cross sectional areas
- increased knee extension strength
- increased 6 minute walk distance
- decreased time to descend stairs safely
Lecture 13:
What did LaStayo et al’s 2011 study of older cancer survivors & eccentric exercises conclude?
High-force, low perceived exertion may increase muscle size, strength, & power and is feasible for older cancer survivors
Lecture 13:
What is Androgen Deprivation therapy (ADT)?
A widely used management strategy for prostate cancer
Lecture 13:
What are 2 ways Androgen Deprivation Therapy (ADT) is Achieved/done?
1.) Surgical Castration
2.) Medications
- luteinizing hormone-releasing hormone agonist (LHRHa)
- Antiandrogen medications that block androgen receptors
Lecture 13:
When discussing the adverse effects of Androgen Deprivation Therapy (ADT), what 2 things are reduced?
Muscle strength and lean & bone mass
Lecture 13:
When discussing the adverse effects of Androgen Deprivation Therapy (ADT), what 2 things are increased?
Fat mass & fracture risk
Lecture 13:
When discussing the adverse effects of Androgen Deprivation Therapy (ADT), why is it of concern?
Compromises physical function, reduces independence, & can be detrimental to quality of life
Lecture 13:
What did Segal et al study in 2003?
- participants?
- study design?
155 prostate cancer survivors who are scheduled to have ADT for at least 3 months were studied in a randomized controlled trial
Lecture 13:
What were the 2 groups studied in Segal et al’s 2003 study of ADT & prostate survivors?
1.) Control group
2.) Exercise group - in 12 week resistance program where they worked 60-70% of their 1RM 3x/week through 9 exercises
Lecture 13:
What were the results of Segal et al’s 2003 study of ADT & prostate survivors?
- increased msucular fitness
- reduced fatigue
- monitors influence of PA & ADT treatment to see if it interferes (no interference occurred)
Lecture 13:
In non ADT individuals, how does resistance training influence testosterone levels?
Resistance training leads to acute testosterone release
Lecture 13:
What happens to testosterone levels during resistance training when someone is receiving ADT?
Resistance training does not compromise testosterone suppression
- improved physical function occurs due to increased serum growth hormone & DHEA (dehydroepiandrosterone)
