Complete story — includes the ending
When Matthew complains that his pants are too tight, he realizes he's gained a little weight and Christine offers to train him. Turns out her "protein shakes" were high calorie milkshakes and they've both gained weight. Barb volunteers to train them at her gym: a sweaty, smelly boxing gym. Christine has her butts to work off and Matthew does next to nothing, yet he loses tons of weight and Christine almost none. Also, Richard makes a point of talking to Ritchie in front of the meanie moms, asking Ritchie if he's okay with Richard's impending marriage. When Ritchie says no, Richard is flummoxed as to how to handle the situation.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, The New Adventures of Old Christine season 4. HTML formatting and reference markers removed. · Content license