Grace has been going to the gym to stretch and participate in weight training for 6 months but does not do any other exercises. Which component of physical fitness might she be lacking in, and why?

• A. Body composition, because it's impossible to improve body composition with weigh training alone.
• B. Muscle strength, because 6 months is not long enough to significantly increase strength.
• C. Flexibility because stretching once a day is not enough to improve flexibility.
• D. Cardiorespiratory endurance, because she's not doing any aerobic exercise (cardio).

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the components of physical fitness. Physical fitness is generally divided into five main components: cardiorespiratory endurance, muscular strength, muscular endurance, flexibility, and body composition.
2. Step 2: Analyze Grace's current exercise routine. Grace is participating in weight training and stretching, which primarily target muscular strength and flexibility, respectively.
3. Step 3: Identify the missing component. Cardiorespiratory endurance is improved through aerobic exercises such as running, swimming, or cycling. Since Grace is not engaging in any aerobic activities, this component is likely lacking.
4. Step 4: Explain why aerobic exercise is essential for cardiorespiratory endurance. Aerobic exercises increase the efficiency of the heart, lungs, and circulatory system, which are critical for sustaining prolonged physical activity.
5. Step 5: Conclude that Grace's lack of aerobic exercise is the reason her cardiorespiratory endurance might be insufficient, as her current routine does not address this component of physical fitness.