Needs Analysis. Machar Reid and Miguel Crespo International Tennis Federation LEVEL III COACHES COURSE

Transcription

1 Needs Analysis Machar Reid and Miguel Crespo International Tennis Federation

2 Introduction Principles of physiology Physiological needs analysis Other performance-determining variables Mechanical demands of tennis

3 Principles of physiology Ability to resynthesise ATP relies on 3 energy system: Creatine Phosphate (CrP) system Anaerobic Glycolysis or Lactic acid system Aerobic or oxygen system All 3 energy system can operate at the same time

4 Energy supply for tennis play 1 Energy currency of the body is ATP; energy is liberated during ATP breakdown to activate muscle fibres to shorten; oxygen is not required. HOWEVER, minimal ATP is stored in cells with only enough energy to perform maximum exercise for several seconds (i.e. sprint for a drop shot, ) CHEMICAL ENERGY FOR ATP RESYNTHESIS LIPIDS CARBOHYDRATES CREATINE PHOSPHATE ATP and PCr provide energy for 10 seconds of maximum intensity activity. After that other processes must provide for ATP formation: the glycolytic and oxidative combustion of fuels.

5 Energy supply for tennis play 2 ATP production through the breakdown of glucose (glycolysis). Glucose/glycogen glucose-6-phosphate (enzyme) pyruvic acid lactic acid + energy 1 molecule of glucose = 2 molecules of ATP. In all-out sprint events lasting 1 or 2 min: blood LA can increase from a resting value of about 1 mmol.kg -1 to more than 25 mmol.kg -1. LA ACCUMULATION: Impairs glycolytic enzyme function to inhibit further glucose breakdown. Decreases the fibres calcium-binding capacity to impede muscle contraction.

6 Lactic Acid Is lactic accumulation specific to muscles used? RESEARCH Putman et al. (1999) 1. Lactate in the deltoid muscle was increased 2-fold immediately following maximal leg exercise and remained elevated 15 minutes post-exercise 2. Non-working muscle mass helps provide energetic homeostasis by metabolizing LA produced by working muscles

7 Energy supply for tennis play 3 Oxidative production of ATP: provides muscles with a steady supply of energy to repeatedly produce force. 1 molecule of glucose = 38 molecules of ATP (39 if the process begins with glycogen) Aerobic metabolism = the primary method of energy production during endurance events.

8 So how does each system contribute to tennis? Overall metabolic response resembles prolonged moderate-intensity exercise (Bergeron et al., 1991). Therefore, although ATP and CrP supply immediate energy during a rally, recovery is sufficient for the aerobic energy system to replenish the depleted energy depots. RESEARCH TELLS US: bursts of effort during a match 70-90% of the time the ball is out of play (work = 3-8 seconds, rest = 20 & 90 seconds) Mean heart rates approximate 60-80% of HR max Mean O2 consumption: 23.1±3.1 ml.kg -1.min -1 (56 % of VO 2 max) for women and; 25.6±2,8 ml.kg -1.min -1 (54 % of VO 2 max) for men. No differences in O2 consumption when serving and returning; O2 consumption dropped during changeovers compared to playing phases but remained significantly elevated compared to the resting periods.

9 HOW HIGH DO BLOOD LACTATE LEVELS RISE IN TENNIS?? LA of elite tennis players in practice matches to be around 2.1±1.0 mmol/l. In matchplay, LA were slightly higher at 2.9±1.3 mmol/l. The highest lactate value found was 7.5 mmol/l. CONCLUSION: contribution of the anaerobic-lactic energy system to the total energy supply during practice matches is 10% and increases to 20% during matchplay.

10 IN CONCLUSION, IT CAN BE STATED THAT TENNIS IS AN INTERMITTENT, NON-CYCLICAL ANAEROBIC SPORT (10-20%), WITH AN AEROBIC RECOVERY PHASE (80-90%).

11 Types of Muscles Fibers Type I (Slow Twitch or Red Fibres) aerobic metabolism to produce ATP Endurance athletes Fibre type conversion not possible Type IIa (Fast Oxidative Fibres) Type IIb (Fast Twitch or White Fibres) larger then Type I fibres anaerobic glycolysis to produce ATP

12 Types of Muscle Fibres

13 But what other variables that influence the Gender physiological profile of matchplay Age Gamestyle Surface

14 GENDER VARIABLES TO CONSIDER HEIGHT males 10-12cm taller ENDURANCE VO2 max of males is 10% larger (relative to lean body mass) females have 10% less h globin AND males have greater CO and SV as well as lung capacity (relative to body size) FAT % difference in essential fat depots (males = 3% and females = 12%) STRENGTH females have less muscle mass contributing to their 55-70% of male absolute strength. Relative strength difference of 20%.

15 Age Physiological development; metabolic efficiency; varied game demands Game style Different strategies + movement demands O Donoghue & Ingram (2001)

16 Effect of Court Surface AVERAGE RALLY DURATION Women s singles matches ~ 7.1 seconds Men s singles matches ~ 5.2 seconds Clay courts ~ 6 seconds Hard courts ~ 4 seconds Grass courts ~ 2.8 seconds PROPORTION OF BASELINE RALLIES French Open 51% Australian Open 46% US Open 35% Wimbledon 19% O Donoghue & Ingram (2001)

17 Mechanical demands of the game STROKES SKILL MOVEMENT VELOCITY GOALS PRECISION PROCESS JOINT ACTION MUSCLES INVOLVED TYPE OF CONTRACTION SPEED OF CONTRACTION REPETITION

18 Adapting specifically! ADAPTATION: the body will adapt to stresses that are appropriately applied; specific to the imposed demand of the activity. SPECIFICITY METABOLIC Relates to length/intensity of work and rest intervals. Average work interval should equate to average point duration. MECHANICAL Relates to using muscles specific to the way they are used on court. Velocity specific training is a form of mechanical specificity.

19 Providing for adaptation through: Volume: total amount of training. Decreases progressively as competition approaches. Intensity: sport-specific intensities likely produce the greatest increases in performance. Measures: HR, rating of perceived exertion. Frequency: number of training sessions per training block. Largely dependent on goals of the training and period of the training year. Density: describes the relationship between the work and recovery phases of conditioning expressed per unit of time. Individuality: musculoskeletal/physiological make-up, injury history, style of play, Recovery: without appropriate recovery the player will not adapt to the stress of training; with too much recovery, the player will not adapt at optimal pace. Variety: A variety of exercises should be selected within the limits of specificity!

20 Loading: the body should be loaded at a frequency, intensity or duration higher than the level to which it is accustomed. T O T A L OVERTRAINING On-court training (matches and practice) W O R K Off-court training L O A D Preparation Precompetitive Competitive Peaking Figure 1. Total workload (on-court plus off-court training) should remain as high as possible to promote maximal adaptation, but should remain below the theoretical level of overtraining.

21 PLANNING & PERIODISATION PERIODISATION o A plan based on scientific principles of program design. o Exhibits control over intensity and volume of training to provide for maximum performance at specific times and to prevent overtraining. o Typically divided into 4 phases: preparation, pre-competitive, competitive and active rest (transition). ASKING THE COACH: What is the difference between linear and undulating periodisation?

22 YPI

23 Periodisation