Possible Clues:

• *Tedious detective duty
• Preparation; walking?
• Hard graft
• Cyclist is propelled by this slog
• Tasks that involve much travelling
• Last to seek dispute, stick up for basic industry
• Support Labour -- it's a hard slog
• Set up pan with a bit of rice in and grind
• Out-of-the-office detective duty
• Hard slog needed to prove effective on stage?