Boston Marathon logo
BOSTON MARATHON 2023

Marlen Rozencwaig

Bib: 20166•F

0:00
0:00
/ mi
Masters
Be the first to cheer!
Overall
#0 / 26622
Gender (Female)
#0 / 11423
Masters (Masters Women)
#0 / 6539
Top 42%
Division (F40-44)
#0 / 1878
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
26:23
Rank: #17509
Start → 5K
26:23 | 8:30/mi
10K· 6.21 mi
52:08
Rank: #17149 (+360)
5K → 10K
25:45 | 8:17/mi
15K· 9.32 mi
1:18:08
Rank: #17089 (+60)
10K → 15K
26:00 | 8:22/mi
20K· 12.43 mi
1:45:19
Rank: #17404 (-315)
15K → 20K
27:11 | 8:45/mi
Half· 13.11 mi
1:51:05
Rank: #17392 (+12)
20K → Half
5:46 | 8:27/mi
25K· 15.53 mi
2:12:05
Rank: #17336 (+56)
Half → 25K
21:00 | 8:40/mi
30K· 18.64 mi
2:39:50
Rank: #17211 (+125)
25K → 30K
27:45 | 8:56/mi
20M
2:52:03
Rank: #17151 (+60)
30K → 20M
12:13 | 8:59/mi
21M
3:01:33
Rank: #17070 (+81)
20M → 21M
9:30 | 9:30/mi
35K· 21.75 mi
3:07:53
Rank: #16988 (+82)
21M → 35K
6:20 | 8:28/mi
23M
3:18:57
Rank: #16871 (+117)
35K → 23M
11:04 | 8:50/mi
24M
3:27:46
Rank: #16862 (+9)
23M → 24M
8:49 | 8:49/mi
40K· 24.85 mi
3:35:16
Rank: #16775 (+87)
24M → 40K
7:30 | 8:46/mi
25.2M
3:38:32
Rank: #16731 (+44)
40K → 25.2M
3:16 | 9:28/mi
Finish· 26.22 mi
3:47:24
Rank: #16723 (+8)
25.2M → Finish
8:52 | 8:42/mi

The Course

Is this your race?

Claim it — unlock a deeper AI report on this race, free

A personalized Race Performance Report that goes beyond this page — emailed to you, built from your real splits.

Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:51:05
Pace8:28 /mi
2nd Half
Distance13.11 mi
Time1:56:19
Pace8:52 /mi
📊Positive Split: 4.7% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:19:0026:238:3026:23
8:30
-
10K
6.21 mi11:44:4552:088:2325:45
8:17
-0:13
15K
9.32 mi12:10:451:18:088:2326:00
8:22
+0:05
20K
12.43 mi12:37:561:45:198:2827:11
8:45
+0:23
Half
13.11 mi12:43:421:51:058:285:46
8:27
-0:18
25K
15.53 mi13:04:422:12:058:3021:00
8:40
+0:13
30K
18.64 mi13:32:272:39:508:3427:45
8:56
+0:16
20M
20.00 mi13:44:402:52:038:3612:13
8:59
+0:03
21M
21.00 mi13:54:103:01:338:399:30
9:30
+0:31
35K
21.75 mi14:00:303:07:538:386:20
8:28
-1:02
23M
23.00 mi14:11:343:18:578:3911:04
8:50
+0:22
24M
24.00 mi14:20:233:27:468:398:49
8:49
-0:01
40K
24.85 mi14:27:533:35:168:407:30
8:46
-0:03
25.2M
25.20 mi14:31:093:38:328:403:16
9:28
+0:42
Finish
26.22 mi14:40:013:47:248:418:52
8:42
-0:46

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

8:17 /mi

Average Pace

8:41 /mi

Slowest Pace

9:30 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:34:38

94% of race

Time at Steady Pace

12:46

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:40 /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 mi11:19:0026:238:3026:23
8:30
#17509
10K
6.21 mi11:44:4552:088:2325:45
8:17
#17149
15K
9.32 mi12:10:451:18:088:2326:00
8:22
#17089
20K
12.43 mi12:37:561:45:198:2827:11
8:45
#17404
Half
13.11 mi12:43:421:51:058:285:46
8:27
#17392
25K
15.53 mi13:04:422:12:058:3021:00
8:40
#17336
30K
18.64 mi13:32:272:39:508:3427:45
8:56
#17211
20M
20.00 mi13:44:402:52:038:3612:13
8:59
#17151
21M
21.00 mi13:54:103:01:338:399:30
9:30
#17070
35K
21.75 mi14:00:303:07:538:386:20
8:28
#16988
23M
23.00 mi14:11:343:18:578:3911:04
8:50
#16871
24M
24.00 mi14:20:233:27:468:398:49
8:49
#16862
40K
24.85 mi14:27:533:35:168:407:30
8:46
#16775
25.2M
25.20 mi14:31:093:38:328:403:16
9:28
#16731
Finish
26.22 mi14:40:013:47:248:418:52
8:42
#16723
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF40-44Seg. OverallSeg. FemalesSeg. F40-44
5K3.11 mi3.11 mi175096258625816973(Top 64%)5894(Top 52%)5894(Top 314%)
10K6.21 mi3.10 mi17149+3606021+2376021+23716864(Top 63%)5787(Top 51%)5787(Top 308%)
15K9.32 mi3.11 mi17089+605963+585963+5816973(Top 64%)5894(Top 52%)5894(Top 314%)
20K12.43 mi3.11 mi17404-3156162-1996162-19918416(Top 69%)6741(Top 59%)6741(Top 359%)
Half13.11 mi0.68 mi17392+126158+46158+417487(Top 66%)6170(Top 54%)6170(Top 329%)
25K15.53 mi2.42 mi17336+566145+136145+1317173(Top 65%)6101(Top 53%)6101(Top 325%)
30K18.64 mi3.11 mi17211+1256084+616084+6116836(Top 63%)5971(Top 52%)5971(Top 318%)
20M20.00 mi1.36 mi17151+606070+146070+1416502(Top 62%)5867(Top 51%)5867(Top 312%)
21M21.00 mi1.00 mi17070+816032+386032+3815979(Top 60%)5623(Top 49%)5623(Top 299%)
35K21.75 mi0.75 mi16988+825985+475985+4715167(Top 57%)5218(Top 46%)5218(Top 278%)
23M23.00 mi1.25 mi16871+1175946+395946+3915223(Top 57%)5304(Top 46%)5304(Top 282%)
24M24.00 mi1.00 mi16862+95961-155961-1516316(Top 61%)5979(Top 52%)5979(Top 318%)
40K24.85 mi0.85 mi16775+875925+365925+3614972(Top 56%)5287(Top 46%)5287(Top 282%)
25.2M25.20 mi0.35 mi16731+445910+155910+1515138(Top 57%)5392(Top 47%)5392(Top 287%)
Finish26.22 mi1.02 mi16723+85915-55915-516518(Top 62%)6109(Top 53%)6109(Top 325%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 64%
×21stories
+97ft-345ft

Overall

16973

Females

5894

F40-44

5894

5K→10K

3.1 - 6.2 mi

Top 63%
×5stories
+79ft-138ft

Overall

16864

Females

5787

F40-44

5787

10K→15K

6.2 - 9.3 mi

Top 64%
×3stories
+67ft-78ft

Overall

16973

Females

5894

F40-44

5894

15K→20K

9.3 - 12.4 mi

Top 69%
×5stories
+106ft-86ft

Overall

18416

Females

6741

F40-44

6741

20K→Half

12.4 - 13.1 mi

Top 66%
×2stories
+19ft-37ft

Overall

17487

Females

6170

F40-44

6170

Half→25K

13.1 - 15.5 mi

Top 65%
×4stories
+66ft-88ft

Overall

17173

Females

6101

F40-44

6101

25K→30K

15.5 - 18.6 mi

Top 63%
×9stories
+181ft-148ft

Overall

16836

Females

5971

F40-44

5971

30K→20M

18.6 - 20.0 mi

Top 62%
×5stories
+64ft-50ft

Overall

16502

Females

5867

F40-44

5867

20M→21M

20.0 - 21.0 mi

Top 60%
×8stories
+106ft-24ft

Overall

15979

Females

5623

F40-44

5623

21M→35K

21.0 - 21.8 mi

Top 57%
×7stories
+17ft-86ft

Overall

15167

Females

5218

F40-44

5218

35K→23M

21.8 - 23.0 mi

Top 57%
×5stories
+23ft-63ft

Overall

15223

Females

5304

F40-44

5304

23M→24M

23.0 - 24.0 mi

Top 61%
×6stories
+12ft-82ft

Overall

16316

Females

5979

F40-44

5979

24M→40K

24.0 - 24.9 mi

Top 56%
×1story
+6ft-20ft

Overall

14972

Females

5287

F40-44

5287

40K→25.2M

24.9 - 25.2 mi

Top 57%
×1story
+13ft-16ft

Overall

15138

Females

5392

F40-44

5392

25.2M→Finish

25.2 - 26.2 mi

Top 62%
×2stories
+22ft-21ft

Overall

16518

Females

6109

F40-44

6109

Passing Analysis

Category:
Athletes Passed
2019
Passed By
1233
Net Change
+786
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#17509
5K → 10K539179+360#17509#17149
10K → 15K218158+60#17149#17089
15K → 20K92407-315#17089#17404
20K → Half3119+12#17404#17392
Half → 25K14892+56#17392#17336
25K → 30K231106+125#17336#17211
30K → 20M10444+60#17211#17151
20M → 21M12847+81#17151#17070
21M → 35K10018+82#17070#16988
35K → 23M14124+117#16988#16871
23M → 24M6859+9#16871#16862
24M → 40K10215+87#16862#16775
40K → 25.2M517+44#16775#16731
25.2M → Finish6658+8#16731#16723
TOTALS20191233+786
📊

Passing Visuals

Category:
Loading...

🔥Passing Intensity

Loading...

🔄Passing Circle

Loading...

🌊Position Flow

Loading...

🏃Race Lanes

Loading...

Upload your GPX file

Supports Garmin, Apple Watch, Polar, Suunto, COROS, Strava, and other apps

.gpx files up to 10MB

Export Track Data

Download your race performance as a GPX or TCX file to import into Strava, Garmin Connect, or other fitness apps.

Questions or issues regarding timing data?

If you notice any discrepancies in your timing data or have questions about your results, our support team can help.

Contact Race Support
Share Feedback

Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing