MED221 Sports Medicine Revision Notes

Section A: Multiple Choice Questions

  • Section A is worth 30% of the overall exam.
  • Comprises 20 multiple-choice questions, each worth 1.5 marks.
  • Students answer all questions in the answer booklet.
  • Example question: Which of the following proteins can be measured to diagnose concussion?
    • a. Creatine kinase (CK)
    • b. IGF-1
    • c. CRP
    • d. GFAP
  • Another Example: Which drug is most likely to be covered by a therapeutic use exemption?
    • a. Testosterone
    • b. Clenbuterol
    • c. Adderall
    • d. Stanozolol

Section B: Long Answer Questions

  • Section B is worth 70% of the overall exam.
  • Comprises 10 long answer questions.
  • Students must choose 5 questions to answer.
  • Each question is of equal weighting.
  • Answers should be limited to 250 words each.
  • Instructions:
    • Open book exam; consult textbooks, papers, and notes.
    • Only in-text citations using author/s name/s and year format are required; no reference list or other bibliography.
    • Provide answers in a single new document (Microsoft Word or PDF format).
    • Do not include name or Student ID in the file name.
  • Example Questions:
    • An athlete wants to use sports supplements. Outline strategies to ensure they do not take something on the WADA banned list.
    • Explain how to monitor overtraining in an elite female athlete, referencing different methods.
    • Outline the ethical challenges of transgender athletes competing in female sport.
    • Describe the process an athlete must undertake to obtain a Therapeutic Use Exemption (TUE) to compete.
    • Explain why anabolic steroids can negatively affect the health of athletes in the long term.
    • Outline the testing you would undertake with an elite footballer to determine if they are fit to return to play after a knee injury.
    • Explain the ethical considerations when developing an anti-doping strategy for sport.
    • Explain how RED-S (relative energy deficiency) differs from the female athlete triad.
    • Explain the molecular mechanisms of how a diuretic could help a mixed-martial art athlete make weight.
    • Outline how a concussion differs from a haemorrhagic stroke and how the former might be treated.

Ergogenic Aids

Carnitine

  • Molecule that transports fatty acids into mitochondria.
  • Dual role:
    • Required for long-chain fatty acid oxidation.
    • Shuttles accumulated acyl groups out of mitochondria.
  • Takes 12 weeks of carnitine supplementation to increase muscle carnitine.
  • Must take with food to promote insulin response.
  • Stephens et al. (2007) J Physiol, 581, 431-444
  • Wall et al. (2011) J Physiol, 589, 963-973
  • 11%↑11\% \uparrow Fig 1: Maximal performance test in carnitine vs. control
  • Mechanism: Carnitine alters fuel metabolism
    • At low intensities, carnitine spares muscle glycogen by increasing fat breakdown.
    • At high intensity = lower lactate accumulation, increased PDC activity.
    • More efficient CHO metabolism; ↑ performance

Creatine

  • Found in a mixed diet including meat and fish (1g/d).
  • Made in the liver, pancreas, and kidneys (1g/d).
  • 20g creatine/d for >5d increases muscle creatine by 25% and Pcr resynthesis during recovery by 35%.
  • Good for short, high intensity exercise.
  • Greenhaff et al. (1994) AJP, 266, 725-730

Caffeine

  • Was first banned in 1962 then removed and/or limits placed after this date.
  • Stimulant to CNS.
  • Fat mobilization (lipolysis).
  • Improved endurance exercise.
  • Reduced muscle glycogenolysis.
  • Increased diuresis.

Anabolic Steroids

  • Anabolic androgenic steroids = steroids for short.
  • Increase muscle mass and strength.
  • Main endogenous (natural) steroid hormone produced by the body is testosterone.
  • Athletes taking steroids either take testosterone directly or synthetic variations to exert the same effect.
  • Mechanism of steroid-induced protein synthesis
    • Steroid hormone (S) passes through the plasma membrane.
    • Inside the target cell, the steroid hormone binds to a specific receptor protein in the cytoplasm or nucleus.
    • The receptor/steroid hormone complex enters the nucleus and binds to DNA, causing gene transcription.
    • Protein synthesis is induced.
    • Protein is produced.

Diuretics

  • Increase rate of urine flow + sodium excretion to adjust volume and composition of body fluids.
  • Used for two main reasons:
    • Rapid weight loss (make weight, increase VO2VO_2max).
    • Masking agents.
  • Most common = Furosemide and hydrochlorothiazide.
  • Cadwallader et al. (2010) Br J Pharmacol. 2010 Sep; 161(1): 1–16.
  • Mechanism of action: Diuretics work in the kidney
    • Distal tubule = Na+Na^+/Cl−Cl^- symporter inhibitors.
    • Collecting duct = Na+Na^+ channel inhibitors.
    • Loop of Henle diuretics = Na+Na^+/K+K^+/2Cl−Cl^- symporter inhibitors.
    • Felker (2011) Heart Failure Reviews, 17, 305-11

Side Effects

  • Caffeine:
    • Pelchovitz et al. (2011) Am J Med, 124, 284-289
    • Myers (1991) Annals Int Med, 114, 147-150
  • Anabolic steroids:
    • Cardiovascular: Lipid profile changes, elevated blood pressure, decreased myocardial function.
    • Endocrine: Gynecomastia, decreased sperm count, testicular atrophy, impotence and transient infertility.
    • Genitourinary (Males): Reduced sperm counts, decreased testicular size.
    • Genitourinary (Females): Menstrual irregularities, clitoromegaly, masculinization.
    • Both: Gynecomastia, libido changes.
    • Dermatological: Acne, male pattern baldness.
    • Hepatic: Increased risk of liver tumors and liver damage.
    • Musculoskeletal: Premature epiphyseal plate closure, increased risk of tendon tears, intramuscular abscess.
    • Psychological: Mania, depression, aggression, mood swings.
    • Hoffman et al. (2006). Journal of Sports Science & Medicine, 5, 182-193
  • Diuretics:
    • CA inhibitors: Metabolic acidosis, Urinary alkalosis
    • Osmotic diuretic: Extracellular water expansion
    • Loop diuretics: Hypokalemia, hypovolemia, hyponatremia, hypomagnesemia, hypocalcemia, precipitate gout, alkalosis
    • Thiazide diuretics: Hypokalemia, hyponatremia, hypovolemia, hypomagnesemia, hypercalcemia, precipitate gout, hyperlipidemia, hyperglycemia
    • K-sparing diuretic: Gynaecomastia, hyperkalaemia, Metabolic acidosis., GIT upset and peptic ulcer
  • Amphetamines side effects:
    • Psychological: Insomnia, Aggressive behavior, Paranoia, Incessant conversations, Decreased appetite, Increased alertness, Irritability, Slurred speech, Dizziness, Confusion, Hallucinations, Obsessive behaviors, Depression, Panic attacks
    • Systemic: Hyperthermia, Malnutrition, Impaired immune system
    • Circulatory: High blood pressure, Vessel damage in brain, Clotting and stroke
    • Heart: Chest pain, Rapid heart rate, Heart attack
    • Liver: Damage
    • Eyes: Dilated pupils
    • Mouth: Grinding of teeth
    • Skin: Sweating, Numbness
    • Respiratory: Shortness of breath
    • Muscular: Jerky movements, Increased activity, Convulsions, Loss of coordination
    • Kidneys: Damage
    • Lombardo (2016). The Physician and Sports Med, 14, 128-139

Monitoring Athletes

Symptoms of Overtraining

  • Underperformance
  • Muscle weakness
  • Chronic fatigue
  • Sore muscles
  • Increased RPE during exercise
  • Reduced motivation
  • Sleep disturbance
  • Increased sleeping heart rate
  • Altered mood states
  • Loss of appetite· GI disturbance
  • Recurrent infection
  • Gleeson. (2002). J Sports Med Sci, 1, 31-41

Blood Markers of Overtraining

  • Plasma glutamine = indicator of excessive training (Rowbottom et al. 1996)
  • Plasma urea = measure of N waste indicating muscle breakdown (Kinderman, 1986)
  • Cortisol/testosterone ratio = overtraining is a catabolic state (Eichner, 1995)
  • Nocturnal catecholamine excretion reduced in overtraining (Foster & Lehmann, 1999)
  • Gleeson. (2002). J Sports Med Sci, 1, 31-41

Training Load Variables in Football

  • Acceleration
  • Total distance
  • Distance >5.5m/s
  • Estimated metabolic power
  • Heart rate exertion
  • Akenhead et al. (2016). Int J Sports Physiol & Perf, 11, 587-593

Determining Fatigue/Fitness

  • Acute:Chronic Workload Ratio
    • WORKLOAD IN LAST 7 DAYS / AVERAGE WORKLOAD OVER LAST 28 DAYS

Acute:Chronic Workload Ratio

  • 'Sweet Spot': ↓ injury risk
  • 'Danger Zone': ↑ injury risk
  • Bourdon et al. (2017). Int J Sports Physiol & Perf, 12,161

TUEs (Therapeutic Use Exemptions)

  • Mainly used for treatment of cardiac conditions
  • Only necessary for sports that prohibit them
  • Rarely granted for use during shooting Beta-blockers
  • Fitch (2012). Clin Med, 12, 257-260
  • Used in treatment of polycystic ovary syndrome (PCOS) in females and hypertension
  • Renal disorders sometimes require diuretic use
  • A TUE should never be granted for an athlete in a sport with weight categories
  • Diuretics
  • Fitch (2012). Clin Med, 12, 257-260

Beta-2 Agonists

  • Act as ligands to adrenergic receptors (highly selective for the beta-2 receptors)
  • Activates a transmembrane signal cascade through adenylyl cyclase
  • Ultimately this reduces Ca2+Ca^{2+} sensitivity, inhibits myosin light chain phosphorylation + prevents muscle contraction
  • Tashkin & Fabbri (2010). Respiratory Research, 11, 149

Beta Agonists and Fat Metabolism

  • Salbutamol increases resting metabolic rate
  • Increases fat oxidation
  • Increases lipolysis
  • Good for fatty acid partitioning i.e. promotes leanness
  • 4 wk terbutaline (5mg/30kg BM twice daily) promotes loss of 1.4kg fat mass
  • Hostrup et al. (2015). J Appl Physiol, 119,475-486
  • Vaisman et al. (1987). J Pediatr, 111,137-139
  • Hoeks et al. (2003). AJP Endo, 285, E775-E782
  • Gaugg et al. (2017). J Breath Res, 11, 046004

Common Adverse Findings

  • Clenbuterol and terbutaline most common adverse findings
  • Hostrup et al. (2020). Drug testing and analysis, 12, 597-609

Corticosteroids

  • Mimic hormones naturally produced by the adrenal gland (hydrocortisone and cortisone)
  • Reduce swelling and inflammation
  • Also reduce the activity of the immune system
  • 2 types:
    • Glucocorticoids: suppress inflammation and immunity
    • Mineralocorticoids: regulate balance of salt and water

Prednisolone and Performance

  • 10 male athletes did 2 cycling trials at 70-75% VO2VO_2max until exhaustion
  • Placebo (lactose) or Prednisolone 60mg/d for 1wk
  • Time to exhaustion increased with Prednisolone: 75 vs 46 mins
  • Glucose and insulin higher with prednisolone
  • Blood lactate higher with prednisolone
  • Arlettaz et al. (2007). Med Sci Sports Ex, 39, 1672-1678

Revision Pointers

  • This content from today is not the only content in the exam
  • You must revise ethical issues in sports medicine
  • You must revise the mechanisms of concussion and how they are assessed in Sport
  • Familiarise yourself with the WADA banned list and how the TUE process works