Slice each chicken breast in half lengthwise to make four thin cutlets, then gently pound each to an even thickness of about 1/4 inch.
In a shallow dish, whisk together the kosher salt, garlic powder, and dried Italian herb blend; stir in the low-fat Italian dressing.
Place the cutlets in the dressing mixture and turn to coat; marinate for at least 1 hour in the refrigerator.
In a second shallow dish, beat the egg until smooth.
In a third shallow dish, combine the whole-wheat breadcrumbs and grated Parmesan cheese.
Working one at a time, dip each marinated cutlet into the beaten egg, letting excess drip off, then press into the breadcrumb-Parmesan mixture to coat evenly.
Preheat the air fryer to 400°F (200°C).
Arrange breaded cutlets in a single layer in the air-fryer basket without overcrowding; cook for 4 minutes.
Flip each cutlet, lightly spray with olive oil, and continue to air fry for another 4 minutes, or until golden brown and an instant-read thermometer registers 165°F (74°C).
Remove the cutlets from the air fryer and serve hot.
