| Clue | Source | Date |
|---|---|---|
| Knee-bending exercise | Newsday | 09 Mar 2022 |
| Exercise involving a push-up position | LA Times Daily | 22 Dec 2020 |
| Exercise involving a push-up position | The Washington Post | 22 Dec 2020 |
| Exercise also called a 'burpee' | Wall Street Journal | 17 Dec 2018 |
| Exercise also called a "burpee" | ||
| Calisthenics exercise |