Lactate Testing in Swimming Genadijus Sokolovas, Ph.D., Global Sport Technology, Inc www.globalsporttechnology.org info@globsport.org Where does lactate come from? • High intensity muscle contractions trigger anaerobic glycolysis • Lactic acid is a by-product of anaerobic glycolysis in muscle cells (non-oxidative way) • 99% of lactic acid turn into the lactate under normal conditions • Lactate is the anion of lactic acid Hard Swimming High Intensity Swimming (1-3 min swim) O2 deficit Lactic Acid (Lactate), H+, Pi, AMP, ADP Acid Environment, lower pH Decreased Swimming Velocity Decreased Muscles Contraction Ability, Inhibited Enzymes’ Activity Lactate Testing • Lactate Peak (La max) • Lactate Clearance • Lactate – Swimming Intensity Lactate Testing in Swimming © Global Sport Technology, Inc LACTATE PEAK • Lactate is a by-product of anaerobic glycolysis • There is a strong correlation between lactate and swimming velocity • Sprinters have more fast twitch muscle fibers and produce larger amounts of lactate • The shorter the swimming distance, (except the 50) the higher amount of lactate is produced © Global Sport Technology, Inc LACTATE PEAK AFTER RACES • Average lactate peaks after the races on various distances (men) Distance, 50 FR meters Lactate Peak, mmol/l 100 FR 200 FR 400 FR 1500 FR 10 KM 7.2 ± 1.1 12.3 ±3.1 11.4 ±2.0 10.3 ± 2.7 7.3 ± 1.3 3.6 ± 1.4 © Global Sport Technology, Inc LACTATE PEAK AND FATIGUE • Lactate peak depends on muscles fatigue. If after multiple races or intense swimming workouts athletes don’t replenish the glycogen, peak lactate will be lower. • Since peak lactates have a high correlation with swimming velocity, athlete’s performances might be lower as well. Therefore, it is important to replenish muscle glycogen before the next race. © Global Sport Technology, Inc Changes of Lactate Peak During a Season 12 La, mmol/L 10 8 Taper – low volume, high intensity 6 4 High total (aerobic) workload volume 2 0 0 5 10 15 Weeks 20 25 LACTATE PEAK AND DIET • Increased intake of carbohydrates has been linked to larger stores of muscles glycogen which provides more fuel for anaerobic metabolism, therefore resulting in a greater production of lactate. © Global Sport Technology, Inc LACTATE PEAK AND TRAINING • High volume and low intensity training reduces the athletes ability to produce peak lactates, but improves lactate clearance. • Swimmers are able to produce and tolerate higher lactate peaks during the lower volume/higher intensity phase of training. © Global Sport Technology, Inc LACTATE PEAK AND AGE • Before and during the process of biological maturation, younger athletes don’t have the enzymatic process in place to cultivate anaerobic metabolism. • Mature athletes rely more on anaerobic metabolism. They can also tolerate higher peak lactates by pushing themselves over the limits during workouts and races. © Global Sport Technology, Inc TOTAL TIME OF RECOVERY • Total Time of Recovery may be evaluated as a rate of lactate removal or the time it takes to remove the lactate from the bloodstream. • As we developed Lactate Clearance database, we introduced a new method to evaluate the Lactate Clearance rate based on the time it took to reach 2 mmol/l of lactate in the blood (Total Time of Recovery) © Global Sport Technology, Inc TOTAL TIME OF RECOVERY AND FATIGUE • Swimming multiple events at a swim meet may • • increase the Total Time of Recovery. By swimming several races in one session, swimmers don’t have enough time to replenish muscles glycogen. Lower amounts of glycogen will lead to lower peak lactates, which ultimately may affect the Total Time of Recovery. © Global Sport Technology, Inc Monitoring of Aerobic/Anaerobic Endurance • Monitoring of aerobic/anaerobic endurance is important for sprinters, middle distance, and distance swimmers • Lactate Clearance test after standard swimming sets: – Peak lactate (anaerobic power) – Rate of lactate clearance and total time of recovery (aerobic endurance and fatigue) • Lactate Clearance testing once a week is enough to monitor aerobic/anaerobic changes Peak Lactates • If peak lactates increase, anaerobic power is higher. It is especially important for sprinters. The higher peak lactates, the higher storage of muscles glycogen. • If peak lactates decrease, more aerobic system (the most efficient) is used. • Peak lactates should be analyzed in conjunction with swimming results in the test sets Lactates Clearance 14 11.7 12 La, mmol/l 10 9.1 8 6 5.2 4 2 0 0 5 10 15 20 25 30 Min • Total Time of Recovery to reach 2 mmol/l line has a high correlation with individual swimming performances: the faster swim, the longer recovery. Low/High Cost of Performances 4:07.98 58.00 53.00 Recovery Time, min 48.00 4:09.70 4:05.83 43.00 4:09.27 4:09.47 38.00 33.00 4:07.83 4:05.65 4:08.38 4:09.82 28.00 4:12.174:13.09 4:14.67 23.00 18.00 4:03.65 4:05.38 4:07.10 4:08.83 4:10.56 Tim e, sec 4:12.29 4:14.02 4:15.74 Low/High Cost of Performances 34.00 2:03.61 Recovery Time, min 32.00 30.00 1:58.56 2:00.72 28.00 2:03.00 2:04.95 26.00 2:02.56 24.00 2:09.16 22.00 20.00 1:57.50 1:59.23 2:00.96 2:02.69 2:04.42 Tim e, sec 2:06.14 2:07.87 2:09.60 2:11.33 COST OF SWIMMING PERFORMANCE © Global Sport Technology, Inc Use of Low/High Cost of Performances Chart • If the individual performance is in a Low Cost Zone, athletes can maintain higher training stress. – Sprinters can do more anaerobic and sprint sets – Middle distance and distance swimmers can do more anaerobic and aerobic sets • If the individual performance is in a High Cost Zone, athletes should focus more on aerobic work and recovery. © Global Sport Technology, Inc Lactate – Swimming Intensity • Blood lactate accumulation during incremental • exercise test Determination of lactate threshold (anaerobic threshold) • Lactate Threshold (LT) – the point (swimming intensity) where the anaerobic system is recruited to contribute more to the energy production, accumulation of lactate in the blood Lactate – Swimming Intensity 12 10 La, mmol/L Lactate Threshold 8 6 4 2 0 1 1.1 1.2 1.3 1.4 V, M/S 1.5 1.6 1.7 Types of Lactate Thresholds • LT at fixed blood lactate concentrations: • 2.0 mmol/L, 2.5 mmol/L, 3.0 mmol/L, 4.0 mmol/L • Individual LT – deflection point on the blood lactate versus swimming velocity curve LT at Fixed Lactate Concentrations • Testing procedure: • Incremental swimming set consisting of two stages • Each stage requiring 300 (age group swimmers) or • • 400 (senior swimmers) M/Y continuous swimming followed by 2 min rest Stage 1 corresponds to 75% of maximum swimming velocity Stage 2 corresponds to the maximum swimming velocity Calculation of Swimming Velocities • Best time on 400 – 4:05.00 (245 Sec). • Maximum swimming velocity: 400 M / 245 Sec = 1.633 M/Sec • 75% of maximum swimming velocity: 1.633 x 0.75 = 1.225 M/Sec • This corresponds to the swimming time on 400 M: 400 M / 1.225 M/Sec = 326.5 Sec (5:26.50) LT at Fixed Lactate Concentrations Easy pace – 75% from max on 400 14 La, mmol/L 12 Max pace on 400 10 Deterioration of Working Capacity 8 6 Improvement of Working Capacity 4 2 0 1 1.1 1.2 1.3 1.4 V, M/S 1.5 1.6 1.7 LT at Fixed Lactate Concentrations • Advantages: • Small number of blood samples (two is enough) • Easy to manage with large group of swimmers • Minimizing problems with detecting deflection point on “lactate – velocity” curve LT at Fixed Lactate Concentrations • Disadvantages: • It is impossible to evaluate individual LT • No individual energy zones Individual LT • Advantages: • Evaluation of individual • 10 La, mmol/L swimming velocities for development of aerobic and anaerobic endurance It is possible to calculate individual borders for various energy zones Deflection Point of the blood lactate curve – Individual Lactate Threshold 12 8 6 4 2 0 1 1.1 1.2 1.3 1.4 V, M/S 1.5 1.6 1.7 Individual LT • Disadvantages: • Time consuming testing of lactate (at least 4 stages) • Complex analysis and evaluation of individual LT and borders between energy zones Lactate – Swimming Intensity 14 La, mmol/L 12 10 Deterioration of Working Capacity 8 6 Improvement of Working Capacity 4 2 0 1 1.1 1.2 1.3 V, M/S 1.4 1.5 1.6 1.7 Lactate/Heart Rate Profile • It is an intermittent incremental exercise swimming test consisting of 4 to 6 stages, each requiring 200 or 300 m/y of continuous swimming followed by 2 min of rest • 5 stages correspond to 75%, 81%, 87%, 93%, and 100% of 200 m/y (sprinters and middle distance swimmers) or 300 m/y (distance swimmers) velocity. Stroke rate and heart rate are determined during the swimming portion of each stage. Lactate is determined immediately after each stage Lactate/Heart Rate Profile • LT is defined as the point where the primary energy system being utilized shifts from aerobic to anaerobic • The test is followed by a 23 min inactive recovery period during which lactate is recorded • Results of this procedure allow the determination of individual LT, an indicator of aerobic-anaerobic fitness, and lactate clearance rate, an indicator of aerobic fitness. The VEL and/or HR at which LT occurs can be translated to individual VEL and/or HR in each energy system Lactate/Heart Rate Profile 7 Swimming Recovery 6 La, Mmol/l 5 Beginning of season 4 Before taper 3 2 1 LA increasing LA clearance 0 Velocity-Time Lactate/Heart Rate Profile 6 Swimming Heart Rate 5 LA, Mmol/l Recovery 4 3 SP1-2 ILT 2 1 EN2-3 EN1 REC 0 1.2 1.3 1.4 1.5 1.6 Velocity-Time 1.7 1.8 1.9