Fatigue & Recovery

Causes of Fatigue Depletion of energy stores ATP CP stores Glycogen stores Lactic acid accumulation (and hydrogen ions) Dehydration & reduced electrolyte concentrations Increased muscle temperature CNS Inhibition Transmitter tiredness Mental fatigue

Depletion CP Stores ATP CP system dominant between 0-6 secs Much power is quickly developed by using this system Creatine phosphate stored in muscle is rapidly depleted Predominant energy system then becomes anaerobic glycolysis system Between 10-20 secs. PC stored in muscles

Depletion of Glycogen Stores When the aerobic system is used continually during exercise glycogen stores are reduced Fats then become the dominant fuel source which requires greater amounts of oxygen to break down & produce ATP & fatigue sets in Have between 60-90 minutes of glycogen stored within the body during continuous activity

Metabolic By Product Accumulation As the rate of anaerobic glycolysis increases so does H+ and LA accumulation within the muscle fibres & in the blood The presence of H+ and LA inhibits muscle contraction & fatigue occurs H+ and LA cause the burning sensation in the muscles

Dehydration (& reduced electrolyte concentration) The body looses fluid through sweat Sweat contains electrolytes, salts & water Dehydration can cause fatigue to coordination, endurance & decision making

Increased Muscle Temperature Causes blood to be redirected away from the working muscles to the skin in an attempt to cool the body Therefore oxygen supply to the working muscles is reduced Increased body temperature can affect decision making

CNS Inhibition Central nervous system inhibition When brain detects fatigue in the muscle it reduces the number and intensity of the messages to the muscle to decrease the contractions to prevent muscle damage

Transmitter Tiredness Fatigue causes the release of the chemical acetylcholine (Ach) to decrease Acetylcholine is the chemical that travels across the neuromuscular synapse (the junction between the nerves and muscles) which assists in the stimulation of the muscle to contract Less acetylcholine means the muscle contracts less

Mental Fatigue Tends to be associated with other forms of fatigue Can make the athlete focus more on feeling tired rather than concentrating on their performance In some instances boredom can also lead to mental fatigue

Recovery Possibilities Active cool down Diet Fluid Ice Massage Hot/cold showers Water session Stretching

Active Cool Down Recovery Eg low intensity jogging Undertaking low intensity active recovery increases speed of LA removal compared to passive recovery Active recovery breaks down 50% blood LA in 10-15min. compared with 30 min. if passive) Active recovery prevents venous pooling Assists in reducing muscle soreness

Diet (replenishment of fuel stores) Following exercise athlete should consume high glycemic foods to replace glycogen quickly Later continue with low glycemic foods Foods high in protein can assist muscle regeneration

Fluid Intake (rehydration) Drink before, during and after training or competition Sports drinks are good during because contain some carbohydrate and electrolytes To increase desire to drink ensure it is flavoured, cool and contains some sodium

Ice Apply ice to bruised/sore/injured soft tissue area to prevent blood flow to area and reduce swelling Ice also prevents inflammation (redness) and reduces pain Ice vests can assist in reducing temperature to more normal levels

Massage Massage can assist blood supply to an area, decrease soreness and return muscle to normal length However an injured area should not be massaged before 48-72 hours after the injury (apply ice)

Hot/Cold Showers Some athletes alternate hot and cold showers (eg 1 min hot, 1 min cold, 1 min hot etc) This can stimulate the nervous and vascular activity to the muscles removing lactic acid and bringing nutrients to the muscles improving recovery

Water Session Eg swimming pool walking, swimming activities This reduces the stress on the joints whilst allowing the athlete to move freely Spas can also be used to massage and increase blood supply to the muscles

Stretching During cool down and in the days following competition & training Prevents muscle stiffness, reduce soreness and returns muscle to it’s normal length