LGA 507 Exercise Physiology Image by Randy Lemoine
LGA 507 Exercise Physiology Image by Randy Lemoine Image by Lionoche Intermittent Vs Continuous Exercise
Aims and Objectives Investigate how intermittent exercise fatigue influences performance Understand the demands of intermittent exercise Aims and Objectives Look at the metabolic responses to intermittent exercise Investigate why intermittent specific tests are more appropriate measure of performance.
Physiology of Intermittent Exercise • Exercise patterns in multiple sprint sports • Recovery between sprints • Restoration of PCr • Lactate accumulation and glycogen depletion • Causes of fatigue • Metabolic changes after sprint training Image by Carine 06
Time Motion Analysis in Football • 25% walking • 37% jogging • 20% cruising • 11% sprinting • 7% moving backwards Image by Nadi 0 Teach people new skills, techniques and strategies - Variety of different teaching methods and styles specific to • Heart athleterate 157 beats/min (70% VO (Reilly and Thomas, 2 max) suitable - Have knowledge and 1976) experience • 15 m sprints every 90 s • 30 sprints per match • Cruising or sprinting every 30 s • Change in activity every 5 s
Loughborough Intermittent Shuttle Test (LIST) (Nicholas et al. , 2000) Set 1 Set 2 Set 3 Set 4 Set 5 Set 6 • Duration 90 mins • Distance covered 12. 5 km Walking @ 1. 5 m. s-1 Sprinting Recovery Running @ ~ 95% VO 2 • 624 changes of direction • Sprint 8% of distance Running @ ~ 55% VO 2 One cycle of the LIST (11 cycles = 1 set) • Energy expenditure = 1400 kcal • Mean oxygen uptake = 70% VO 2 max
Yo-Yo Intermittent Recovery Test (Bangsbo, 1994) What is the difference between the Yo-Yo test and the bleep test? Adapted from Krustrup et al. (2003)
Treadmill Protocol (Drust et al. , 2000)
Metabolism in the Recovery Periods During Intermittent Exercise Performance in subsequent sprints will be affected by: Teach people new skills, techniques and strategies These are largely -determined Variety of different teaching by: methods and styles specific to athlete • Intensity and duration of -exercise Have suitable knowledge and experience • Time available for recovery Resting or active recovery • Restoration of muscle ATP and PCr • Clearance of H+ and lactate • Restoration of muscle myoglobin O 2 stores • Restoration of electrolyte (Na+) balance • Maintenance of muscle temperature It takes only a few minutes to reach this target value. When the value is reached and the oxygen cost is comfortably met, by jonthescone we refer to this. Image as steady rate oxygen uptake. Image by Paul Nicholson
Sprint Performance in Intermittent Exercise How often do we sprint in football match play? 30 s maximal cycling with 4 min recovery Glycolysis contribution due to build up of H+ and lactate High intensity performance Spriet et al. (1989)
Sprint Performance in Intermittent Exercise Continued. . . Images Adapted from Gaitanos et al. (1993) By the 10 th Trial…… Pcr stores – not enough recovery time to resynthesise Use of aerobic system What does an increase in the use of the aerobic system mean for speed of ATP resynthesis and power output?
6 Second Sprints With 30 s Recovery Why do lactate levels reduce by post trial 10? Gaitanos et al. (1993)
Nutritional Support What does this mean for tournaments? How does this influence game preparation? Saltin and Karlsson 1973
Carbohydrate Diets Saltin and Karlsson 1973
Fatigue in Football Temporary fatigue after short intense periods of activity – reduced PCr availability. Image by toksuede Teach people new skills, techniques and strategies end ofteaching the game -Towards Variety ofthe different – low muscle glycogen in to methods and styles specific some muscle fibres and athlete dehydration and -maybe Have suitable knowledge reduction in central function. experience Early phase of second half – lower muscle temperature than at the end of the first half.
Effects of Fatigue on Practical Performance The players of better teams in Serie A performed more short passes during games than players from lower ranked Serie A teams. Teach people new skills, techniques and strategies -Why Variety of different is this an issueteaching for methods and styles specific to fitness coaches? athlete -Are Have suitable knowledge adaptations able to and experience occur? Match related intermittent exercise fatigue induced a decline in short passing ability (Rampinini et al. , 2008). It takes only a few minutes to reach this target value. When the value is reached and the oxygen cost is comfortably met, we refer to this as steady rate oxygen uptake. Image by Image iguanaby joe. Paul Nicholson
Can Adaptations to Sprint Training Occur? • Increased peak and mean power in 30 s sprint test • Increased contribution from glycolysis in a 30 s sprint test • Increased PFK activity • Nevill et al. (1989)
High Intensity Interval Training……. • Increase muscle buffering capacity (maintain p. H levels) • Increased monocarboxylate transporter (MCT) activity (important to remove H+ and lactate) • Increase in creatine kinase activity – up to 10 -15% after 2 weeks of training • Decrease recovery time between sprint = Increased performance Weston et al. (1997)
Need for Position Specific Training? Full backs covered significantly more distance than central defenders in low speed (11. 1 -14 km. h), moderate speed (14. 119 km. h), high speed (19. 1 -23 km. h) and sprinting (>23 km. h) speed zones. In team sports do training sessions focus on specific positional groups? Central midfielders covered significantly more distance than central defenders and full backs in the low and moderate speed zones. Lago-Penas et al. (2009) Forwards and central midfielders covered significantly more distance in the sprinting speed zone than other positions.
Summary With repeated sprints the anaerobic contribution declines while the aerobic contribution stays the same or increases. With repeated sprints the rate of muscle Pcr breakdown decline due to incomplete resynthesis in recovery periods. Depletion of glycogen is likely to affect performance when intermittent Teach people new skills, high intensity exercise is performed over a 3. prolonged Hydrogenperiod. in the cell combines techniques and strategies with two coenzymes (NAD - Variety of different teaching and FAD) that carry it to the methods and styles specific to electron transport chain. athlete High intensity training muscle anaerobic and buffering capacity. Onesuitable molecule of glycogen -5. Have knowledge and can generate 37 molecules of ATP. experience
References Bangsbo, J. Mohr, M. Krustrup, P. (2006). Physical and metabolic demands of training and match-play in the elite football player. Journal of Sports Sciences, 24 (7), pp. 665. Ekblom, B. (1986). Applied physiology of soccer. Sports Medicine, 3, pp. 50 - 60. Gaitanos, G. C. Williams, C. Boobis, L. H. Brooks, S. (1993). Human muscle metabolism during intermittent maximal exercise. Journal of Applied Physiology, 75 (2), pp. 712 -719. Krustrup, P. Mohr, M. Amstrup, T. Rysgaard, T. Johansen, J. Steensberg, A. Pedersen, P. K. Bangsbo, J. (2003). The Yo-Yo intermittent recovery test is highly reproducible, sensitive, and valid. Medicine and Science in Sports and Exercise, 35 (12), pp. 2120. Krustrup, P. Mohr, M. Steensberg, A. Bencke, J. Kjaer, M. Bangsbo, J. (2006). Muscle and Blood Metabolites during a Soccer Game: Implications for Sprint Performance. Medicine and Science in Sports and Exercise, 38 (6), pp. 1165 -1174. Lago-Penas, C. Rey, E. Lago-Ballesteros, J. Casais, L. and Dominguez, E. (2009). Analysis of work rate in soccer according to playing positions. International journal of Performance Analysis of Sport, 9, pp. 218 -227. Mohr, M. Krustrup, P. Bangsbo, J. (2005). Fatigue in soccer: A brief review. Journal of Sports Sciences, 23 (6), pp. 593.
References Nevill, M. E. Boobis, L. H. Brooks, S. and Williams, C. (1989). Effect of training on muscle metabolism during treadmill sprinting. Journal of Applied Physiology, 67 (7), pp. 2376 -2382. Nicholas, C. W. Nuttall, F. E. Williams, C. (2000). The Loughborough Intermittent Shuttle Test: A field test that simulates the activity pattern of soccer. Journal of Sports Science, 18 (2), pp. 97 -104. Rampinini, E. Impellizzeri, F. M. Castagna, C. Azzalin, A. Bravo, D. F. and Wisløff, U. (2008). Effect of match related fatigue on short passing ability in young soccer players. Medicine and Science in Sport and Exercise, 40(5), pp. 934 -942. Reilly, T. and Thomas, V. (1976). A motion analysis of work rate in different positional roles in professional match play. Journal of Human Movement Studies, 2, pp. 87 -97. Weston, A. R. Myburgh, K. H. Lindsay, F. H. Dennis, S. C. Noakes, T. D. and Hawley, J. A. (1996). Skeletal muscle buffering capacity and endurance performance after high-intensity interval training by well-trained cyclists. European Journal of Applied Physiology and Occupational Physiology, 75 (1), pp. 7 -13.
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