Table 5 Multi-level regression analyses for change in swimming speed for 50 m, 100 m, and 200 m in swimmers at national level across years for women and men (Model 1) with correction for multiple participations (Model 2) and age of athletes with multiple participations (Model 3)

50 m women long course

1

0.002

0.001

0.218

2.524

0.013

2

0.002

0.001

0.218

2.524

0.013

3

0.001

0.001

0.179

2.086

0.039

50 m women short course

1

0.003

0.001

0.334

4.011

< 0.001

2

0.003

0.001

0.334

4.011

< 0.001

3

0.003

0.001

0.266

3.381

< 0.001

50 m men long course

1

0.007

0.001

0.491

6.368

< 0.001

2

0.007

0.001

0.491

6.368

< 0.001

3

0.007

0.001

0.488

6.647

< 0.001

50 m men short course

1

0.005

0.001

0.330

3.956

< 0.001

2

0.005

0.001

0.330

3.956

< 0.001

3

0.005

0.001

0.363

4.612

< 0.001

100 m women long course

1

0.002

0.001

0.237

2.765

0.007

2

0.002

0.001

0.237

2.765

0.007

3

0.002

0.001

0.220

2.613

0.010

100 m women short course

1

0.002

0.001

0.279

3.285

0.001

2

0.002

0.001

0.279

3.285

0.001

3

0.002

0.001

0.268

3.233

0.002

100 m men long course

1

0.006

0.001

0.536

7.182

< 0.001

2

0.006

0.001

0.536

7.182

< 0.001

3

0.006

0.001

0.528

7.234

< 0.001

100 m men short course

1

0.006

0.001

0.495

6.445

< 0.001

2

0.006

0.001

0.495

6.445

< 0.001

3

0.006

0.001

0.472

6.392

< 0.001

200 m women long course

1

0.002

0.001

0.205

2.371

0.019

2

0.002

0.001

0.205

2.371

0.019

3

0.002

0.001

0.220

2.647

0.009

200 m women short course

1

0.001

0.001

0.056

0.640

0.524

2

0.001

0.001

0.056

0.640

0.524

3

0.001

0.001

0.119

1.357

0.177

200 m men long course

1

0.004

0.001

0.427

5.337

< 0.001

2

0.004

0.001

0.427

5.337

< 0.001

3

0.005

0.001

0.440

5.462

< 0.001

200 m men short course

1

0.005

0.001

0.451

5.715

< 0.001

2

0.005

0.001

0.451

5.715

< 0.001

3

0.005

0.001

0.465

5.918

< 0.001