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BOSTON MARATHON 2023

Jonathan Kalus

Bib: 29129•M

MA

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

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
32:53
Rank: #24909
Start → 5K
32:53 | 10:35/mi
10K· 6.21 mi
1:05:01
Rank: #24645 (+264)
5K → 10K
32:08 | 10:21/mi
15K· 9.32 mi
1:37:42
Rank: #24603 (+42)
10K → 15K
32:41 | 10:31/mi
20K· 12.43 mi
2:11:27
Rank: #24544 (+59)
15K → 20K
33:45 | 10:52/mi
Half· 13.11 mi
2:19:32
Rank: #24655 (-111)
20K → Half
8:05 | 11:51/mi
25K· 15.53 mi
2:46:28
Rank: #24588 (+67)
Half → 25K
26:56 | 11:07/mi
30K· 18.64 mi
3:22:39
Rank: #24477 (+111)
25K → 30K
36:11 | 11:39/mi
20M
3:38:23
Rank: #24407 (+70)
30K → 20M
15:44 | 11:35/mi
21M
3:51:13
Rank: #24381 (+26)
20M → 21M
12:50 | 12:50/mi
35K· 21.75 mi
3:59:31
Rank: #24335 (+46)
21M → 35K
8:18 | 11:06/mi
23M
4:14:12
Rank: #24311 (+24)
35K → 23M
14:41 | 11:44/mi
24M
4:25:24
Rank: #24276 (+35)
23M → 24M
11:12 | 11:12/mi
40K· 24.85 mi
4:35:34
Rank: #24264 (+12)
24M → 40K
10:10 | 11:53/mi
25.2M
4:39:44
Rank: #24245 (+19)
40K → 25.2M
4:10 | 12:05/mi
Finish· 26.22 mi
4:50:45
Rank: #24230 (+15)
25.2M → Finish
11:01 | 10:49/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:19:32
Pace10:39 /mi
2nd Half
Distance13.11 mi
Time2:31:13
Pace11:32 /mi
📊Positive Split: 8.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:50:4332:5310:3532:53
10:35
-
10K
6.21 mi12:22:511:05:0110:2832:08
10:21
-0:14
15K
9.32 mi12:55:321:37:4210:2932:41
10:31
+0:10
20K
12.43 mi13:29:172:11:2710:3533:45
10:52
+0:21
Half
13.11 mi13:37:222:19:3210:398:05
11:51
+0:59
25K
15.53 mi14:04:182:46:2810:4326:56
11:07
-0:44
30K
18.64 mi14:40:293:22:3910:5236:11
11:39
+0:32
20M
20.00 mi14:56:133:38:2310:5515:44
11:35
-0:04
21M
21.00 mi15:09:033:51:1311:0112:50
12:50
+1:15
35K
21.75 mi15:17:213:59:3111:018:18
11:06
-1:44
23M
23.00 mi15:32:024:14:1211:0314:41
11:44
+0:38
24M
24.00 mi15:43:144:25:2411:0411:12
11:12
-0:32
40K
24.85 mi15:53:244:35:3411:0510:10
11:53
+0:41
25.2M
25.20 mi15:57:344:39:4411:064:10
12:05
+0:12
Finish
26.22 mi16:08:354:50:4511:0611:01
10:49
-1:16

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

10:21 /mi

Average Pace

11:06 /mi

Slowest Pace

12:50 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:22:28

49% of race

Time at Steady Pace

46:26

16% of race

Time at Slower Pace

1:41:51

35% of race

Average Pace: 11:05 /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 mi11:50:4332:5310:3532:53
10:35
#24909
10K
6.21 mi12:22:511:05:0110:2832:08
10:21
#24645
15K
9.32 mi12:55:321:37:4210:2932:41
10:31
#24603
20K
12.43 mi13:29:172:11:2710:3533:45
10:52
#24544
Half
13.11 mi13:37:222:19:3210:398:05
11:51
#24655
25K
15.53 mi14:04:182:46:2810:4326:56
11:07
#24588
30K
18.64 mi14:40:293:22:3910:5236:11
11:39
#24477
20M
20.00 mi14:56:133:38:2310:5515:44
11:35
#24407
21M
21.00 mi15:09:033:51:1311:0112:50
12:50
#24381
35K
21.75 mi15:17:213:59:3111:018:18
11:06
#24335
23M
23.00 mi15:32:024:14:1211:0314:41
11:44
#24311
24M
24.00 mi15:43:144:25:2411:0411:12
11:12
#24276
40K
24.85 mi15:53:244:35:3411:0510:10
11:53
#24264
25.2M
25.20 mi15:57:344:39:4411:064:10
12:05
#24245
Finish
26.22 mi16:08:354:50:4511:0611:01
10:49
#24230
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi24909144991449924491(Top 92%)14292(Top 94%)14292(Top 270%)
10K6.21 mi3.10 mi24645+26414389+11014389+11024373(Top 92%)14250(Top 94%)14250(Top 270%)
15K9.32 mi3.11 mi24603+4214357+3214357+3224491(Top 92%)14292(Top 94%)14292(Top 270%)
20K12.43 mi3.11 mi24544+5914319+3814319+3824413(Top 92%)14234(Top 94%)14234(Top 269%)
Half13.11 mi0.68 mi24655-11114362-4314362-4325760(Top 97%)14806(Top 98%)14806(Top 280%)
25K15.53 mi2.42 mi24588+6714329+3314329+3324140(Top 91%)14092(Top 93%)14092(Top 267%)
30K18.64 mi3.11 mi24477+11114266+6314266+6324052(Top 90%)13992(Top 92%)13992(Top 265%)
20M20.00 mi1.36 mi24407+7014225+4114225+4123634(Top 89%)13756(Top 91%)13756(Top 260%)
21M21.00 mi1.00 mi24381+2614204+2114204+2123879(Top 90%)13836(Top 91%)13836(Top 262%)
35K21.75 mi0.75 mi24335+4614171+3314171+3323457(Top 88%)13589(Top 90%)13589(Top 257%)
23M23.00 mi1.25 mi24311+2414155+1614155+1623614(Top 89%)13682(Top 90%)13682(Top 259%)
24M24.00 mi1.00 mi24276+3514133+2214133+2223406(Top 88%)13536(Top 89%)13536(Top 256%)
40K24.85 mi0.85 mi24264+1214127+614127+623752(Top 89%)13672(Top 90%)13672(Top 259%)
25.2M25.20 mi0.35 mi24245+1914113+1414113+1422639(Top 85%)13152(Top 87%)13152(Top 249%)
Finish26.22 mi1.02 mi24230+1514101+1214101+1223626(Top 89%)13637(Top 90%)13637(Top 258%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 92%
×21stories
+97ft-345ft

Overall

24491

Males

14292

M18-39

14292

5K→10K

3.1 - 6.2 mi

Top 92%
×5stories
+79ft-138ft

Overall

24373

Males

14250

M18-39

14250

10K→15K

6.2 - 9.3 mi

Top 92%
×3stories
+67ft-78ft

Overall

24491

Males

14292

M18-39

14292

15K→20K

9.3 - 12.4 mi

Top 92%
×5stories
+106ft-86ft

Overall

24413

Males

14234

M18-39

14234

20K→Half

12.4 - 13.1 mi

Top 97%
×2stories
+19ft-37ft

Overall

25760

Males

14806

M18-39

14806

Half→25K

13.1 - 15.5 mi

Top 91%
×4stories
+66ft-88ft

Overall

24140

Males

14092

M18-39

14092

25K→30K

15.5 - 18.6 mi

Top 90%
×9stories
+181ft-148ft

Overall

24052

Males

13992

M18-39

13992

30K→20M

18.6 - 20.0 mi

Top 89%
×5stories
+64ft-50ft

Overall

23634

Males

13756

M18-39

13756

20M→21M

20.0 - 21.0 mi

Top 90%
×8stories
+106ft-24ft

Overall

23879

Males

13836

M18-39

13836

21M→35K

21.0 - 21.8 mi

Top 88%
×7stories
+17ft-86ft

Overall

23457

Males

13589

M18-39

13589

35K→23M

21.8 - 23.0 mi

Top 89%
×5stories
+23ft-63ft

Overall

23614

Males

13682

M18-39

13682

23M→24M

23.0 - 24.0 mi

Top 88%
×6stories
+12ft-82ft

Overall

23406

Males

13536

M18-39

13536

24M→40K

24.0 - 24.9 mi

Top 89%
×1story
+6ft-20ft

Overall

23752

Males

13672

M18-39

13672

40K→25.2M

24.9 - 25.2 mi

Top 85%
×1story
+13ft-16ft

Overall

22639

Males

13152

M18-39

13152

25.2M→Finish

25.2 - 26.2 mi

Top 89%
×2stories
+22ft-21ft

Overall

23626

Males

13637

M18-39

13637

Passing Analysis

Category:
Athletes Passed
1252
Passed By
573
Net Change
+679
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#24909
5K → 10K35490+264#24909#24645
10K → 15K143101+42#24645#24603
15K → 20K11960+59#24603#24544
20K → Half4115-111#24544#24655
Half → 25K10740+67#24655#24588
25K → 30K15443+111#24588#24477
30K → 20M8414+70#24477#24407
20M → 21M5529+26#24407#24381
21M → 35K537+46#24381#24335
35K → 23M4622+24#24335#24311
23M → 24M4712+35#24311#24276
24M → 40K3321+12#24276#24264
40K → 25.2M223+19#24264#24245
25.2M → Finish3116+15#24245#24230
TOTALS1252573+679
📊

Passing Visuals

Category:
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🔥Passing Intensity

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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