When you climb, the aerobic and anaerobic systems work at the same time rather than taking turns, and each time you let go to move, blood flow brings oxygen into the forearm and carries metabolites away. As Lattice puts it, the aerobic system needs volume and the anaerobic system needs intensity; climbing until you're pumped out lands in between and trains neither. Below critical force you can keep climbing; above it, the clock starts.
No study answers when to start. Eva López asks for 2+ years of structured climbing and a 15-second hang on a 25 mm edge; MacLeod says grade is irrelevant and circumstances matter; Lattice says beginners should build finger strength by climbing. Every hangboard study used intermediate-to-advanced climbers. Finger strength goes up, but in Stien 2024 bouldering performance did not follow. If you start: twice a week, 48–72 hours apart, sets progressing 2-3-4-4 over four weeks, no hangs in week five.
Beyond your fingers, pulling strength in the shoulders and back also tracks grade: in a 2025 National Taiwan University thesis on 25 advanced men, only weighted pull-up relative to body weight predicted grade. Train bodyweight pull-ups until you can do 10; Lattice sees diminishing returns above 165% of body weight (135% for women). Campus thresholds differ: Gresham wants two years of bouldering and hangboarding and about V6/7 before going feet-off; the UIAA says 8–10 years of climbing. No feet-off or dynamic campusing under 18 is advice shared by the BMC and the UIAA.
Climbing until you're pumped and falling off is not endurance training: Lattice argues it lands between the aerobic and anaerobic systems and trains neither well. If you pump out on easy terrain and can't recover at rests, start with ARC or long intervals at an intensity that barely pumps you. If you can't link one hard section, that's when 4×4s or 1 on 1 off power-endurance work comes in. Lattice, Eva López and Liu Chun-yen disagree on whether ARC should produce a light pump. Support for these methods comes mainly from physiology and coaching experience; no controlled trial has compared them head to head.
Periodization is simply organising training over time. With three sessions a week, start with three rules: in each session do the strongest, hardest work first and the low-intensity work last; leave 48–72 hours between finger-heavy sessions; when you add something new, take something else out. Then group 3–4 weeks into a mesocycle and make the last week a deload, cutting total load by 40–60% rather than resting completely. Anderson's linear model trains one quality at a time; Bechtel argues no quality should be dropped for long. No research in climbing has shown which is better.
There is no dedicated research on home training; this post collects coaching advice from Lattice, Power Company, the BMC and Hooper's Beta. The minimum kit is a doorframe pull-up bar plus a hangboard or lifting block. Until you're experienced, keep hangboard sessions under 20 minutes and take weight off with your feet on a chair; use the bar for pull-ups and lock-offs and the floor for press-ups and core. Home training can maintain finger strength, but improving still means getting back on the wall.
A 2023 systematic review found that a strength training intervention prevented shoulder and elbow overuse injuries, but the evidence comes from two reports on one cohort of student climbers, and it doesn't apply to fingers. Finger flexor strength averages about six times extensor strength, and only direct extensor training changes that, but the link between the ratio and injury is still speculative. The once-a-week, three-circuit prevention routine (external rotation, core, legs, forearms) is coaching consensus, not a research finding.
Elite climbers are lean on average, but in Lattice's data BMI showed no significant correlation with grade, and they observed that climbers who stay in a long-term calorie deficit struggle to gain finger strength. Several studies find climbers under-eat: in one study of 25 advanced to elite climbers, 28% had low energy availability. Watch three groups of RED-S warning signs: menstrual changes, repeated injury or illness, and training that stops paying off. For recovery, Eva López recommends 48–72 hours between hangboard sessions. If you suspect RED-S, get assessed by a doctor or registered dietitian.