Lactate Testing in Swimming

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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
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