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BOSTON MARATHON 2023

Alissa Underhill

Bib: 19109•F

WA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 47%
Gender (Female)
#0 / 11423
Top 30%
Division (F18-39)
#0 / 4884
Top 48%
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
7:39/mi
23:46
↑ 97↓ 3451.5%
10K· 6.21 mi
7:32/mi
47:10
↑ 79↓ 1380.4%
15K· 9.32 mi
7:36/mi
1:10:46
↑ 67↓ 78
20K· 12.43 mi
7:47/mi
1:34:57
↑ 106↓ 860.1%
Half· 13.11 mi
7:34/mi
1:40:07
↑ 19↓ 370.5%
25K· 15.53 mi
7:56/mi
1:59:22
↑ 66↓ 880.2%
30K· 18.64 mi
8:25/mi
2:25:31
↑ 181↓ 1480.2%
20M
8:34/mi
2:37:10
↑ 64↓ 500.2%
21M
9:37/mi
2:46:47
↑ 106↓ 241.6%
35K· 21.75 mi
8:23/mi
2:53:03
↑ 17↓ 861.7%
23M
8:43/mi
3:03:58
↑ 23↓ 630.6%
24M
8:22/mi
3:12:20
↓ 821.3%
40K· 24.85 mi
8:31/mi
3:19:37
↓ 200.3%
25.2M
9:14/mi
3:22:48
↑ 13↓ 160.2%
Finish· 26.22 mi
7:55/mi
3:30:52
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:40:07
Pace7:38 /mi
2nd Half
Distance13.11 mi
Time1:50:45
Pace8:27 /mi
📊Positive Split: 10.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:15:2723:467:3923:46
7:39
-
10K
6.21 mi11:38:5147:107:3523:24
7:32
-0:07
15K
9.32 mi12:02:271:10:467:3623:36
7:36
+0:04
20K
12.43 mi12:26:381:34:577:3824:11
7:47
+0:11
Half
13.11 mi12:31:481:40:077:385:10
7:34
-0:13
25K
15.53 mi12:51:031:59:227:4119:15
7:56
+0:22
30K
18.64 mi13:17:122:25:317:4826:09
8:25
+0:29
20M
20.00 mi13:28:512:37:107:5111:39
8:34
+0:09
21M
21.00 mi13:38:282:46:477:579:37
9:37
+1:03
35K
21.75 mi13:44:442:53:037:576:16
8:23
-1:14
23M
23.00 mi13:55:393:03:588:0010:55
8:43
+0:20
24M
24.00 mi14:04:013:12:208:018:22
8:22
-0:21
40K
24.85 mi14:11:183:19:378:027:17
8:31
+0:09
25.2M
25.20 mi14:14:293:22:488:033:11
9:14
+0:43
Finish
26.22 mi14:22:333:30:528:038:04
7:55
-1:19

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

7:32 /mi

Average Pace

8:03 /mi

Slowest Pace

9:37 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:07:26

60% of race

Time at Steady Pace

59:43

28% of race

Time at Slower Pace

23:43

11% of race

Average Pace: 8:03 /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 mi11:15:2723:467:3923:46
7:39
#11040
10K
6.21 mi11:38:5147:107:3523:24
7:32
#10846
15K
9.32 mi12:02:271:10:467:3623:36
7:36
#10874
20K
12.43 mi12:26:381:34:577:3824:11
7:47
#11036
Half
13.11 mi12:31:481:40:077:385:10
7:34
#11018
25K
15.53 mi12:51:031:59:227:4119:15
7:56
#11174
30K
18.64 mi13:17:122:25:317:4826:09
8:25
#11670
20M
20.00 mi13:28:512:37:107:5111:39
8:34
#11847
21M
21.00 mi13:38:282:46:477:579:37
9:37
#12205
35K
21.75 mi13:44:442:53:037:576:16
8:23
#12287
23M
23.00 mi13:55:393:03:588:0010:55
8:43
#12444
24M
24.00 mi14:04:013:12:208:018:22
8:22
#12479
40K
24.85 mi14:11:183:19:378:027:17
8:31
#12535
25.2M
25.20 mi14:14:293:22:488:033:11
9:14
#12544
Finish
26.22 mi14:22:333:30:528:038:04
7:55
#12491
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi110402353235311009(Top 41%)2353(Top 21%)2353(Top 48%)
10K6.21 mi3.10 mi10846+1942251+1022251+10210740(Top 40%)2181(Top 19%)2181(Top 45%)
15K9.32 mi3.11 mi10874-282268-172268-1711009(Top 41%)2353(Top 21%)2353(Top 48%)
20K12.43 mi3.11 mi11036-1622349-812349-8111625(Top 44%)2755(Top 24%)2755(Top 56%)
Half13.11 mi0.68 mi11018+182340+92340+910902(Top 41%)2331(Top 20%)2331(Top 48%)
25K15.53 mi2.42 mi11174-1562453-1132453-11312240(Top 46%)3218(Top 28%)3218(Top 66%)
30K18.64 mi3.11 mi11670-4962791-3382791-33813796(Top 52%)4207(Top 37%)4207(Top 86%)
20M20.00 mi1.36 mi11847-1772909-1182909-11814077(Top 53%)4449(Top 39%)4449(Top 91%)
21M21.00 mi1.00 mi12205-3583126-2173126-21716502(Top 62%)5906(Top 52%)5906(Top 121%)
35K21.75 mi0.75 mi12287-823187-613187-6114585(Top 55%)4867(Top 43%)4867(Top 100%)
23M23.00 mi1.25 mi12444-1573295-1083295-10814505(Top 54%)4899(Top 43%)4899(Top 100%)
24M24.00 mi1.00 mi12479-353339-443339-4413648(Top 51%)4467(Top 39%)4467(Top 91%)
40K24.85 mi0.85 mi12535-563396-573396-5713477(Top 51%)4454(Top 39%)4454(Top 91%)
25.2M25.20 mi0.35 mi12544-93403-73403-713828(Top 52%)4639(Top 41%)4639(Top 95%)
Finish26.22 mi1.02 mi12491+533401+23401+211532(Top 43%)3462(Top 30%)3462(Top 71%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 41%
×21story building
+97ft-345ft

Overall

11009

Females

2353

F18-39

2353

5K→10K

3.1 - 6.2 mi

Top 40%
×5story building
+79ft-138ft

Overall

10740

Females

2181

F18-39

2181

10K→15K

6.2 - 9.3 mi

Top 41%
×3story building
+67ft-78ft

Overall

11009

Females

2353

F18-39

2353

15K→20K

9.3 - 12.4 mi

Top 44%
×5story building
+106ft-86ft

Overall

11625

Females

2755

F18-39

2755

20K→Half

12.4 - 13.1 mi

Top 41%
×2story building
+19ft-37ft

Overall

10902

Females

2331

F18-39

2331

Half→25K

13.1 - 15.5 mi

Top 46%
×4story building
+66ft-88ft

Overall

12240

Females

3218

F18-39

3218

25K→30K

15.5 - 18.6 mi

Top 52%
×9story building
+181ft-148ft

Overall

13796

Females

4207

F18-39

4207

30K→20M

18.6 - 20.0 mi

Top 53%
×5story building
+64ft-50ft

Overall

14077

Females

4449

F18-39

4449

20M→21M

20.0 - 21.0 mi

Top 62%
×8story building
+106ft-24ft

Overall

16502

Females

5906

F18-39

5906

21M→35K

21.0 - 21.8 mi

Top 55%
×7story building
+17ft-86ft

Overall

14585

Females

4867

F18-39

4867

35K→23M

21.8 - 23.0 mi

Top 54%
×5story building
+23ft-63ft

Overall

14505

Females

4899

F18-39

4899

23M→24M

23.0 - 24.0 mi

Top 51%
×6story building
+12ft-82ft

Overall

13648

Females

4467

F18-39

4467

24M→40K

24.0 - 24.9 mi

Top 51%
×1story
+6ft-20ft

Overall

13477

Females

4454

F18-39

4454

40K→25.2M

24.9 - 25.2 mi

Top 52%
×1story
+13ft-16ft

Overall

13828

Females

4639

F18-39

4639

25.2M→Finish

25.2 - 26.2 mi

Top 43%
×2story building
+22ft-21ft

Overall

11532

Females

3462

F18-39

3462

Passing Analysis

Category:
Athletes Passed
1213
Passed By
2664
Net Change
-1451
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#11040
5K → 10K398204+194#11040#10846
10K → 15K175203-28#10846#10874
15K → 20K105267-162#10874#11036
20K → Half3517+18#11036#11018
Half → 25K74230-156#11018#11174
25K → 30K63559-496#11174#11670
30K → 20M54231-177#11670#11847
20M → 21M23381-358#11847#12205
21M → 35K22104-82#12205#12287
35K → 23M46203-157#12287#12444
23M → 24M5994-35#12444#12479
24M → 40K3995-56#12479#12535
40K → 25.2M2332-9#12535#12544
25.2M → Finish9744+53#12544#12491
TOTALS12132664-1451
📊

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