Possible Clues:

• Influence
• Bodyguard's asset
• Bodyguards, slangily
• With 44-Across, they're found at the ends of 17-, 25-, 49- and 59-Across
• - of Love (Alice Cooper)
• Biceps, e.g.
• Part of the body which produces movement
• Body tissue - strength
• Strength - to move limbs, etc
• Force; a body tissue