Victor Matfield 115kg

Victor Matfield 100 Tests 27 AUGUST 2010IN SPRINGBOKS Victor Matfield Victor Matfield Birth: 11 May 1977, Pietersburg RSA Height: 200cm Weight: 115kg Position: Lock Provinces: Blue Bulls (1998, 2001 to present), Griquas (1999, 2000) Primary school: Pietersburg-North Secondary school: Pietersburg High Tertiary education: University of Pretoria Test stats Springbok number: 705 Tests: 99 Results: P 99 | W 62 | L 35 | D 2 Points: 30 (6 tries) Captain: 11 Tests (7 wins) Tests started: 95 (4 as replacement) First Test: 30 June 2001 (age 24) v Italy (Port Elizabeth) Last Test: 21 August 2010 (age 33) v New Zealand (Soweto) Honours SA Rugby Player of the Year nominee (2001, 2005, 2006, 2007, 2009) Try of the Year (2004) (v Australia in Durban) Most-capped Springbok lock World record with Bakkies Botha for most Tests as a lock combination in the starting line-up (56)

I read an article ages ago where Bakkies said when they were around 21-22 years old, Matfield was actually heavier than him (Bakkies).  When they became a combination they conditioned to become specialists at 4 and 5 respectively. 
Also, Matfield could bench press more than just about anyone in the team. 

Matfield definitely muscled up unlike lazy Mostert who has no definition or bulk on him Stupid in this day and age

Lazy off the field Moz No gym work clearly

Matfield might have started at 107kg and ended at that weight but at his peak he had muscled up to 115kg. Mostert is 8 to 10kg too light for a modern test lock