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BOSTON MARATHON 2023

Natalia Szlarb

Bib: 11843•F

DC

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 47%
Gender (Female)
#0 / 11423
Top 29%
Division (F18-39)
#0 / 4884
Top 47%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Course Elevation
7–469 ft
≈
×2stacked redwood trees
•▲ 890 ft climb · ▼ 1342 ft descent
Ribbon color based on
FasterSteadySlower· vs. your average pace
Start
0:00
Race begins
5K· 3.11 mi
7:28/mi
23:13
↑ 97↓ 3451.5%
10K· 6.21 mi
7:27/mi
46:22
↑ 79↓ 1380.4%
15K· 9.32 mi
7:31/mi
1:09:42
↑ 67↓ 78
20K· 12.43 mi
7:43/mi
1:33:41
↑ 106↓ 860.1%
Half· 13.11 mi
7:43/mi
1:38:57
↑ 19↓ 370.5%
25K· 15.53 mi
7:52/mi
1:58:01
↑ 66↓ 880.2%
30K· 18.64 mi
8:34/mi
2:24:38
↑ 181↓ 1480.2%
20M
8:38/mi
2:36:22
↑ 64↓ 500.2%
21M
9:12/mi
2:45:34
↑ 106↓ 241.6%
35K· 21.75 mi
8:36/mi
2:52:00
↑ 17↓ 861.7%
23M
8:40/mi
3:02:51
↑ 23↓ 630.6%
24M
8:48/mi
3:11:39
↓ 821.3%
40K· 24.85 mi
8:43/mi
3:19:06
↓ 200.3%
25.2M
9:05/mi
3:22:14
↑ 13↓ 160.2%
Finish· 26.22 mi
8:04/mi
3:30:27
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:38:57
Pace7:33 /mi
2nd Half
Distance13.11 mi
Time1:51:30
Pace8:30 /mi
📊Positive Split: 12.7% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:49:5823:137:2823:13
7:28
-
10K
6.21 mi11:13:0746:227:2823:09
7:27
-0:01
15K
9.32 mi11:36:271:09:427:2923:20
7:31
+0:04
20K
12.43 mi12:00:261:33:417:3223:59
7:43
+0:12
Half
13.11 mi12:05:421:38:577:335:16
7:43
0:00
25K
15.53 mi12:24:461:58:017:3619:04
7:52
+0:09
30K
18.64 mi12:51:232:24:387:4626:37
8:34
+0:42
20M
20.00 mi13:03:072:36:227:4911:44
8:38
+0:04
21M
21.00 mi13:12:192:45:347:539:12
9:12
+0:34
35K
21.75 mi13:18:452:52:007:556:26
8:36
-0:36
23M
23.00 mi13:29:363:02:517:5710:51
8:40
+0:04
24M
24.00 mi13:38:243:11:397:598:48
8:48
+0:08
40K
24.85 mi13:45:513:19:068:017:27
8:43
-0:05
25.2M
25.20 mi13:48:593:22:148:023:08
9:05
+0:22
Finish
26.22 mi13:57:123:30:278:028:13
8:04
-1:01

Checkpoints & Pacing

📈Pace Line

Pace Progression

Track your pace changes throughout the race. Dot colors mark your quickest to easiest segments, relative to your own pace.

Fastest Pace

7:27 /mi

Average Pace

8:02 /mi

Slowest Pace

9:12 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:06:14

60% of race

Time at Steady Pace

1:11:53

34% of race

Time at Slower Pace

12:20

6% of race

Average Pace: 8:02 /mi

Loading chart...
Faster pace (< avg)
Steady pace (≈ avg)
Slower pace (> avg)

🎨Heatmap

Pace Heatmap

Where you sped up and eased off relative to your own pace across the race. Colors are relative to your own range, not to other runners.

Loading...
0mi6.6mi13.1mi19.7mi26.2mi
Pace:
Faster
Steady
Slower

Click or hover over segments to see details

✨Sparklines

Checkpoint Splits with Pace Trends

Overall Pace Trend

CheckpointDistanceTime of DayTimeAvg PaceSegmentPaceTrendRank
5K
3.11 mi10:49:5823:137:2823:13
7:28
#9410
10K
6.21 mi11:13:0746:227:2823:09
7:27
#9694
15K
9.32 mi11:36:271:09:427:2923:20
7:31
#9854
20K
12.43 mi12:00:261:33:417:3223:59
7:43
#10179
Half
13.11 mi12:05:421:38:577:335:16
7:43
#10277
25K
15.53 mi12:24:461:58:017:3619:04
7:52
#10461
30K
18.64 mi12:51:232:24:387:4626:37
8:34
#11244
20M
20.00 mi13:03:072:36:227:4911:44
8:38
#11524
21M
21.00 mi13:12:192:45:347:539:12
9:12
#11731
35K
21.75 mi13:18:452:52:007:556:26
8:36
#11921
23M
23.00 mi13:29:363:02:517:5710:51
8:40
#12052
24M
24.00 mi13:38:243:11:397:598:48
8:48
#12274
40K
24.85 mi13:45:513:19:068:017:27
8:43
#12367
25.2M
25.20 mi13:48:593:22:148:023:08
9:05
#12383
Finish
26.22 mi13:57:123:30:278:028:13
8:04
#12390
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi94101588158810280(Top 39%)1978(Top 17%)1978(Top 40%)
10K6.21 mi3.10 mi9694-2841706-1181706-11810095(Top 38%)1869(Top 16%)1869(Top 38%)
15K9.32 mi3.11 mi9854-1601762-561762-5610280(Top 39%)1978(Top 17%)1978(Top 40%)
20K12.43 mi3.11 mi10179-3251916-1541916-15411091(Top 42%)2457(Top 22%)2457(Top 50%)
Half13.11 mi0.68 mi10277-981964-481964-4812115(Top 46%)2993(Top 26%)2993(Top 61%)
25K15.53 mi2.42 mi10461-1842079-1152079-11511666(Top 44%)2875(Top 25%)2875(Top 59%)
30K18.64 mi3.11 mi11244-7832556-4772556-47714723(Top 55%)4761(Top 42%)4761(Top 97%)
20M20.00 mi1.36 mi11524-2802729-1732729-17314487(Top 54%)4689(Top 41%)4689(Top 96%)
21M21.00 mi1.00 mi11731-2072863-1342863-13414483(Top 54%)4746(Top 42%)4746(Top 97%)
35K21.75 mi0.75 mi11921-1902981-1182981-11815858(Top 60%)5593(Top 49%)5593(Top 115%)
23M23.00 mi1.25 mi12052-1313087-1063087-10614177(Top 53%)4707(Top 41%)4707(Top 96%)
24M24.00 mi1.00 mi12274-2223229-1423229-14216190(Top 61%)5903(Top 52%)5903(Top 121%)
40K24.85 mi0.85 mi12367-933296-673296-6714590(Top 55%)5064(Top 44%)5064(Top 104%)
25.2M25.20 mi0.35 mi12383-163315-193315-1913041(Top 49%)4239(Top 37%)4239(Top 87%)
Finish26.22 mi1.02 mi12390-73343-283343-2812577(Top 47%)3994(Top 35%)3994(Top 82%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 39%
×21story building
+97ft-345ft

Overall

10280

Females

1978

F18-39

1978

5K→10K

3.1 - 6.2 mi

Top 38%
×5story building
+79ft-138ft

Overall

10095

Females

1869

F18-39

1869

10K→15K

6.2 - 9.3 mi

Top 39%
×3story building
+67ft-78ft

Overall

10280

Females

1978

F18-39

1978

15K→20K

9.3 - 12.4 mi

Top 42%
×5story building
+106ft-86ft

Overall

11091

Females

2457

F18-39

2457

20K→Half

12.4 - 13.1 mi

Top 46%
×2story building
+19ft-37ft

Overall

12115

Females

2993

F18-39

2993

Half→25K

13.1 - 15.5 mi

Top 44%
×4story building
+66ft-88ft

Overall

11666

Females

2875

F18-39

2875

25K→30K

15.5 - 18.6 mi

Top 55%
×9story building
+181ft-148ft

Overall

14723

Females

4761

F18-39

4761

30K→20M

18.6 - 20.0 mi

Top 54%
×5story building
+64ft-50ft

Overall

14487

Females

4689

F18-39

4689

20M→21M

20.0 - 21.0 mi

Top 54%
×8story building
+106ft-24ft

Overall

14483

Females

4746

F18-39

4746

21M→35K

21.0 - 21.8 mi

Top 60%
×7story building
+17ft-86ft

Overall

15858

Females

5593

F18-39

5593

35K→23M

21.8 - 23.0 mi

Top 53%
×5story building
+23ft-63ft

Overall

14177

Females

4707

F18-39

4707

23M→24M

23.0 - 24.0 mi

Top 61%
×6story building
+12ft-82ft

Overall

16190

Females

5903

F18-39

5903

24M→40K

24.0 - 24.9 mi

Top 55%
×1story
+6ft-20ft

Overall

14590

Females

5064

F18-39

5064

40K→25.2M

24.9 - 25.2 mi

Top 49%
×1story
+13ft-16ft

Overall

13041

Females

4239

F18-39

4239

25.2M→Finish

25.2 - 26.2 mi

Top 47%
×2story building
+22ft-21ft

Overall

12577

Females

3994

F18-39

3994

Passing Analysis

Category:
Athletes Passed
795
Passed By
3775
Net Change
-2980
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#9410
5K → 10K188472-284#9410#9694
10K → 15K114274-160#9694#9854
15K → 20K71396-325#9854#10179
20K → Half6104-98#10179#10277
Half → 25K90274-184#10277#10461
25K → 30K43826-783#10461#11244
30K → 20M30310-280#11244#11524
20M → 21M35242-207#11524#11731
21M → 35K12202-190#11731#11921
35K → 23M53184-131#11921#12052
23M → 24M21243-222#12052#12274
24M → 40K32125-93#12274#12367
40K → 25.2M3046-16#12367#12383
25.2M → Finish7077-7#12383#12390
TOTALS7953775-2980
📊

Passing Visuals

Category:
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🔄Passing Circle

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🌊Position Flow

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🏃Race Lanes

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Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing