Javier 和 Stella 正在规划他们的健身计划。 Javier 和 Stella 的体重分别为 70 kg 和 60 kg。 图表中展示了这两个人步行和慢跑的速度。

1. Find the total calories burned by each person for the four brisk walks and compare them.

The four walks together take $150$ minutes.

Since $150 \div 30 = 5$, multiply the 30-minute calorie values by $5$.

Using the Walking $6.5$ km/h row:

Javier, $70$ kg: $150 \times 5 = 750$ calories

Stella, $60$ kg: $130 \times 5 = 650$ calories

Difference:
$750 - 650 = 100$

1. Check whether Javier meets the target for additional health benefits.

For Javier's walks:
$\text{time for one walk}=\frac{4}{6}\text{ h}=\frac{2}{3}\text{ h}=40\text{ min}$
$\text{total walking time}=3\times 40=120\text{ min}$

For Javier's jogs:
$\text{time for one jog}=\frac{6}{8}\text{ h}=0.75\text{ h}=45\text{ min}$
$\text{total jogging time}=2\times 45=90\text{ min}$

Since $1$ min vigorous $=2$ min moderate,
$90\text{ min jogging}=180\text{ min moderate-equivalent}$

Total moderate-equivalent time:
$120+180=300\text{ min}$

So Javier meets the target for additional health benefits.

2. Check whether Stella meets the target for optimal health benefits.

For Stella's jogs:
$\text{time for one jog}=\frac{8}{10}\text{ h}=0.8\text{ h}=48\text{ min}$
$\text{total jogging time}=2\times 48=96\text{ min}$

Stella needs at least $75$ min of vigorous-intensity aerobic activity.

Since $96>75$, Stella meets the target for optimal health benefits.

3. Calculate Javier's total calories burned per week.

Javier has mass $70$ kg.

Walking calories: use Walking $6.5$ km/h, $70$ kg: $150$ calories per $30$ min.
$\text{walking calories}=\frac{120}{30}\times 150=600$

Jogging calories: use Jogging $8$ km/h, $70$ kg: $280$ calories per $30$ min.
$\text{jogging calories}=\frac{90}{30}\times 280=840$

Yoga calories:
$45\text{ min}\times 2=90\text{ min}=1.5\text{ h}$
$\text{yoga calories}=1.5\times 3\times 70=315$

Total calories burned by Javier:
$600+840+315=1755$

4. Calculate Stella's total calories burned per week.

Stella has mass $60$ kg.

Jogging calories: use Jogging $9.5$ km/h, $60$ kg: $300$ calories per $30$ min.
$\text{jogging calories}=\frac{96}{30}\times 300=960$

Weight training calories:
$30\text{ min}\times 2=60\text{ min}=1\text{ h}$
$\text{weight training calories}=1\times 4\times 60=240$

Total calories burned by Stella:
$960+240=1200$

5. Compare Javier's calories with Stella's and decide whether Javier's statement is correct.

Difference in calories:
$1755-1200=555$

Percentage more than Stella:
$\frac{555}{1200}\times 100\%=46.25\%$

This is about $50\%$ more.

Both also do muscle-strengthening activities on $2$ days per week, so they meet that part of the advice.