Related Clues:

• Lifter's asset
• Strength
• Biceps, e.g.
• Influence
• Sinew
• Power
• It may be pulled or pumped
• Clout
• Brawn
• Iron-pumper's pride
• Flexor or extensor
• Workout target
• Bodyguards, slangily
• Mover or shaker?
• With 44-Across, they're found at the ends of 17-, 25-, 49- and 59-Across