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BOSTON MARATHON 2023

Sergio Zafra

Bib: 8432 M CO

CA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 38%
Gender (Male)
#0 / 15176
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Ribbon color based on
FasterSteadySlower· vs. your average pace
Start
0:00
Race begins
469 ft elev
5K· 3.11 mi
7:18/mi
22:42
↑ 97↓ 3451.5%
220 ft elev
10K· 6.21 mi
7:41/mi
46:35
↑ 79↓ 1380.4%
157 ft elev
15K· 9.32 mi
7:35/mi
1:10:09
↑ 67↓ 78
146 ft elev
20K· 12.43 mi
7:43/mi
1:34:08
↑ 106↓ 860.1%
165 ft elev
Half· 13.11 mi
7:31/mi
1:39:16
↑ 19↓ 370.5%
148 ft elev
25K· 15.53 mi
7:46/mi
1:58:05
↑ 66↓ 880.2%
127 ft elev
30K· 18.64 mi
8:00/mi
2:22:56
↑ 181↓ 1480.2%
138 ft elev
20M
7:56/mi
2:33:43
↑ 64↓ 500.2%
148 ft elev
21M
8:20/mi
2:42:03
↑ 106↓ 241.6%
227 ft elev
35K· 21.75 mi
7:41/mi
2:47:48
↑ 17↓ 861.7%
156 ft elev
23M
8:05/mi
2:57:55
↑ 23↓ 630.6%
116 ft elev
24M
7:52/mi
3:05:47
↓ 821.3%
34 ft elev
40K· 24.85 mi
7:55/mi
3:12:33
↓ 200.3%
20 ft elev
25.2M
8:16/mi
3:15:24
↑ 13↓ 160.2%
18 ft elev
Finish· 26.22 mi
7:33/mi
3:23:06
↑ 22↓ 21
17 ft elev
Course Elevation
7–469 ft
≈
×2stacked redwood trees
•▲ 890 ft climb · ▼ 1342 ft descent

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:39:16
Pace7:34 /mi
2nd Half
Distance13.11 mi
Time1:43:50
Pace7:55 /mi
📊Positive Split: 4.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:48:0822:427:1822:42
7:18
-
10K
6.21 mi11:12:0146:357:3023:53
7:41
+0:23
15K
9.32 mi11:35:351:10:097:3223:34
7:35
-0:06
20K
12.43 mi11:59:341:34:087:3423:59
7:43
+0:08
Half
13.11 mi12:04:421:39:167:345:08
7:31
-0:12
25K
15.53 mi12:23:311:58:057:3618:49
7:46
+0:15
30K
18.64 mi12:48:222:22:567:4024:51
8:00
+0:14
20M
20.00 mi12:59:092:33:437:4110:47
7:56
-0:04
21M
21.00 mi13:07:292:42:037:438:20
8:20
+0:24
35K
21.75 mi13:13:142:47:487:435:45
7:41
-0:39
23M
23.00 mi13:23:212:57:557:4410:07
8:05
+0:24
24M
24.00 mi13:31:133:05:477:447:52
7:52
-0:13
40K
24.85 mi13:37:593:12:337:456:46
7:55
+0:03
25.2M
25.20 mi13:40:503:15:247:452:51
8:16
+0:21
Finish
26.22 mi13:48:323:23:067:457:42
7:33
-0:43

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

7:18 /mi

Average Pace

7:45 /mi

Slowest Pace

8:20 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:01:48

90% of race

Time at Steady Pace

21:18

10% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:45 /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 mi10:48:0822:427:1822:42
7:18
#8140
10K
6.21 mi11:12:0146:357:3023:53
7:41
#9989
15K
9.32 mi11:35:351:10:097:3223:34
7:35
#10287
20K
12.43 mi11:59:341:34:087:3423:59
7:43
#10469
Half
13.11 mi12:04:421:39:167:345:08
7:31
#10476
25K
15.53 mi12:23:311:58:057:3618:49
7:46
#10487
30K
18.64 mi12:48:222:22:567:4024:51
8:00
#10497
20M
20.00 mi12:59:092:33:437:4110:47
7:56
#10443
21M
21.00 mi13:07:292:42:037:438:20
8:20
#10354
35K
21.75 mi13:13:142:47:487:435:45
7:41
#10317
23M
23.00 mi13:23:212:57:557:4410:07
8:05
#10289
24M
24.00 mi13:31:133:05:477:447:52
7:52
#10268
40K
24.85 mi13:37:593:12:337:456:46
7:55
#10201
25.2M
25.20 mi13:40:503:15:247:452:51
8:16
#10157
Finish
26.22 mi13:48:323:23:067:457:42
7:33
#10069
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi81407069706910869(Top 41%)8585(Top 57%)8585(Top 162%)
10K6.21 mi3.10 mi9989-18498140-10718140-107112098(Top 45%)9150(Top 60%)9150(Top 173%)
15K9.32 mi3.11 mi10287-2988321-1818321-18110869(Top 41%)8585(Top 57%)8585(Top 162%)
20K12.43 mi3.11 mi10469-1828400-798400-7911060(Top 42%)8607(Top 57%)8607(Top 163%)
Half13.11 mi0.68 mi10476-78402-28402-210377(Top 39%)8286(Top 55%)8286(Top 157%)
25K15.53 mi2.42 mi10487-118383+198383+1910774(Top 40%)8381(Top 55%)8381(Top 159%)
30K18.64 mi3.11 mi10497-108331+528331+5210885(Top 41%)8287(Top 55%)8287(Top 157%)
20M20.00 mi1.36 mi10443+548285+468285+469777(Top 37%)7626(Top 50%)7626(Top 144%)
21M21.00 mi1.00 mi10354+898216+698216+699404(Top 35%)7291(Top 48%)7291(Top 138%)
35K21.75 mi0.75 mi10317+378184+328184+329818(Top 37%)7531(Top 50%)7531(Top 142%)
23M23.00 mi1.25 mi10289+288137+478137+4710297(Top 39%)7635(Top 50%)7635(Top 144%)
24M24.00 mi1.00 mi10268+218098+398098+3910252(Top 39%)7525(Top 50%)7525(Top 142%)
40K24.85 mi0.85 mi10201+678041+578041+579416(Top 35%)7043(Top 46%)7043(Top 133%)
25.2M25.20 mi0.35 mi10157+448005+368005+368070(Top 30%)6230(Top 41%)6230(Top 118%)
Finish26.22 mi1.02 mi10069+887928+777928+778944(Top 34%)6722(Top 44%)6722(Top 127%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 41%
×21story building
+97ft-345ft

Overall

10869

Males

8585

M18-39

8585

5K→10K

3.1 - 6.2 mi

Top 45%
×5story building
+79ft-138ft

Overall

12098

Males

9150

M18-39

9150

10K→15K

6.2 - 9.3 mi

Top 41%
×3story building
+67ft-78ft

Overall

10869

Males

8585

M18-39

8585

15K→20K

9.3 - 12.4 mi

Top 42%
×5story building
+106ft-86ft

Overall

11060

Males

8607

M18-39

8607

20K→Half

12.4 - 13.1 mi

Top 39%
×2story building
+19ft-37ft

Overall

10377

Males

8286

M18-39

8286

Half→25K

13.1 - 15.5 mi

Top 40%
×4story building
+66ft-88ft

Overall

10774

Males

8381

M18-39

8381

25K→30K

15.5 - 18.6 mi

Top 41%
×9story building
+181ft-148ft

Overall

10885

Males

8287

M18-39

8287

30K→20M

18.6 - 20.0 mi

Top 37%
×5story building
+64ft-50ft

Overall

9777

Males

7626

M18-39

7626

20M→21M

20.0 - 21.0 mi

Top 35%
×8story building
+106ft-24ft

Overall

9404

Males

7291

M18-39

7291

21M→35K

21.0 - 21.8 mi

Top 37%
×7story building
+17ft-86ft

Overall

9818

Males

7531

M18-39

7531

35K→23M

21.8 - 23.0 mi

Top 39%
×5story building
+23ft-63ft

Overall

10297

Males

7635

M18-39

7635

23M→24M

23.0 - 24.0 mi

Top 39%
×6story building
+12ft-82ft

Overall

10252

Males

7525

M18-39

7525

24M→40K

24.0 - 24.9 mi

Top 35%
×1story
+6ft-20ft

Overall

9416

Males

7043

M18-39

7043

40K→25.2M

24.9 - 25.2 mi

Top 30%
×1story
+13ft-16ft

Overall

8070

Males

6230

M18-39

6230

25.2M→Finish

25.2 - 26.2 mi

Top 34%
×2story building
+22ft-21ft

Overall

8944

Males

6722

M18-39

6722

Passing Analysis

Category:
Athletes Passed
1264*
Passed By
3191
Net Change
-1929
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#8140
5K → 10K111860-1849#8140#9989
10K → 15K87383-298#9989#10287
15K → 20K98280-182#10287#10469
20K → Half3441-7#10469#10476
Half → 25K118129-11#10476#10487
25K → 30K169179-10#10487#10497
30K → 20M101*47+54#10497#10443
20M → 21M13243+89#10443#10354
21M → 35K6831+37#10354#10317
35K → 23M9668+28#10317#10289
23M → 24M6544+21#10289#10268
24M → 40K10942+67#10268#10201
40K → 25.2M56*12+44#10201#10157
25.2M → Finish12032+88#10157#10069
TOTALS1264*3191-1929

* Includes athletes who did not complete a segment (DNF/DNQ).

📊

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