The 4 x 8 group produced the best results, by a significant margin. See the table below for key data. 4 x 16 . 4 x 8. 4 x 4. ... Could the 8-minute repeats work for you?

The 8 times table. Knowing your times tables is really helpful with mental maths and problem solving. The 8 times table is double the 4 times table.