1. In these belt-tightening times, cost-conscious workouts at home and at the gym topped the list of fitness trends for this year in a survey, followed by shorter. more time-efficient regimens, such as boot camp and Circuit training.
本句是一个简单句。句子的主干是 cost-conscious workouts at home and at the gym topped the list of fitness trends.后面followed by...circuit training过去分词短语作伴随状语。such as表示举例。
语法重点：分词短语作状语
2. Boot-camp workouts and circuit training, both of which burn calories while building strength and endurance, will be among the most popular trends in 2010, as time-constrained consumers seek shorter, more intense regimens.
本句是一个复合句，主句是 Boot-camp workouts and circuit training will be among the most popular trends in 2010. which引导非限制性定语从句，修饰Boot-camp workouts and circuit training。其中 while building strength and endurance为时间状语从句的的省略形式，省略了主语。as引导原因状语从句。
语法重点：定语从句，原因状语从句