Cut the lemon in half and remove seeds. Use a lemon reamer to juice. Strain pulp if desired into a large glass. You should get about 1/4 cup lemon juice.
Crush strawberries and add juice to lemon juice. Add low-calorie sweetener and stir. Add water and ice cubes. Garnish with a whole strawberry.
The serving contains about 40 calories, 0.7 g protein, 0 g fat, 10 g carbohydrates, 1.7 g fiber, and 1.2 mg sodium.