The ACME Global Corporation would be violating Title VII of the Civil Rights Act of 1964 if it turned away applicants because of their age, markedly. Title VII denies an organization the ability to turn away applicants for employment based on their race, color, religion, sex, nation of origin, or to limit that applicant's current employment possibilities based on these criteria. (If, however, ACME wanted to make applicants pass a physical stress test for a position and defend reasoning for such, it would not be in violation of federal law to do so. One such example is how firefighters must be able to complete physically exertive acts.)
